1
|
Gavel EH, Barreto G, Hawke KV, Stellingwerff T, James LJ, Saunders B, Logan-Sprenger HM. How Cool is That? The Effects of Menthol Mouth Rinsing on Exercise Capacity and Performance: A Systematic Review and Meta-analysis. SPORTS MEDICINE - OPEN 2024; 10:18. [PMID: 38381237 PMCID: PMC10881929 DOI: 10.1186/s40798-024-00679-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 01/10/2024] [Indexed: 02/22/2024]
Abstract
BACKGROUND Menthol (MEN) mouth rinsing (MR) has gained considerable interest in the athletic population for exercise performance; however, the overall magnitude of effect is unknown. OBJECTIVE The aim of this systematic review and meta-analysis was to determine the efficacy of menthol MEN MR and the impact it has on exercise capacity and performance. METHODS Three databases were searched with articles screened according to the inclusion/exclusion criteria. Three-level meta-analyses were used to investigate the overall efficacy of MEN MR and the impact it has on exercise capacity and performance. Meta-regressions were then performed with 1) mean VO2peak, 2) MEN swilling duration; 3) the MEN concentration of MR solution, 4) the number of executed swills throughout a single experiment, 5) the use of flavoured sweetened, non-caloric, or non-flavoured neutral solutions as controls, 6) mean environmental temperature at the time of exercise tests, and 7) exercise type as fixed factors to evaluate their influence on the effects of MEN MR. RESULTS Ten MEN MR studies included sufficient information pertaining to MEN MR and exercise performance and capacity. MR with MEN resulted in no significant change in capacity and performance (SMD = 0.12; 95% CI - 0.08, 0.31; p = 0.23, n = 1, tau21 < 0.0001, tau22 = < 0.0001, I2 = 0%). No significant influence was detected in meta-regressions for VO2peak, (estimate: 0.03; df = 8; 95% CI - 0.03, 0.09; p = 0.27), swilling duration (5 vs. 10 s: 0.00; df = 16; 95% CI - 0.41, 0.41; p = 1.0), MEN concentration (low [0.01%] vs. high [0.1%]: - 0.08; df = 15; 95% CI - 0.49, 0.32; p = 0.67), number of swills (estimate: 0.02; df = 13; 95% CI - 0.05, 0.09; p = 0.56), the use of flavoured sweetener or non-caloric as control (non-flavoured vs. flavoured: 0.12; df = 16; 95% CI - 0.30, 0.55; p = 0.55) or mean room temperature during exercise tests (estimate: 0.01; df = 16; 95% CI - 0.02, 0.04; p = 0.62). CONCLUSION MEN MR did not significantly improve overall exercise capacity and performance, though those involved in endurance exercise may see benefits.
Collapse
Affiliation(s)
- Erica H Gavel
- Faculty of Science, Ontario Tech University, Oshawa, ON, Canada.
| | - Gabriel Barreto
- Applied Physiology and Nutrition Research Group, Center of Lifestyle Medicine, Faculdade de Medicina FMUSP, Universidade de São Paulo, São Paulo, Brazil
| | - Kierstyn V Hawke
- Faculty of Health Science, Ontario Tech University, Oshawa, ON, Canada
| | - Trent Stellingwerff
- Canadian Sport Institute - Pacific, Victoria, BC, Canada
- Exercise Science, Physical and Health Education, University of Victoria, Victoria, BC, Canada
| | - Lewis J James
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Bryan Saunders
- Applied Physiology and Nutrition Research Group, Center of Lifestyle Medicine, Faculdade de Medicina FMUSP, Universidade de São Paulo, São Paulo, Brazil
- Institute of Orthopaedics and Traumatology, Faculty of Medicine FMUSP, University of São Paulo, São Paulo, Brazil
| | - Heather M Logan-Sprenger
- Faculty of Science, Ontario Tech University, Oshawa, ON, Canada
- Faculty of Health Science, Ontario Tech University, Oshawa, ON, Canada
| |
Collapse
|
2
|
van de Kerkhof TM, Bongers CCWG, Périard JD, Eijsvogels TMH. Performance Benefits of Pre- and Per-cooling on Self-paced Versus Constant Workload Exercise: A Systematic Review and Meta-analysis. Sports Med 2024; 54:447-471. [PMID: 37803106 PMCID: PMC10933154 DOI: 10.1007/s40279-023-01940-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/17/2023] [Indexed: 10/08/2023]
Abstract
BACKGROUND AND OBJECTIVE Exercise in hot environments impairs endurance performance. Cooling interventions can attenuate the impact of heat stress on performance, but the influence of an exercise protocol on the magnitude of performance benefit remains unknown. This meta-analytical review compared the effects of pre- and per-cooling interventions on performance during self-paced and constant workload exercise in the heat. METHODS The study protocol was preregistered at the Open Science Framework ( https://osf.io/wqjb3 ). A systematic literature search was performed in PubMed, Web of Science, and MEDLINE from inception to 9 June, 2023. We included studies that examined the effects of pre- or per-cooling on exercise performance in male individuals under heat stress (> 30 °C) during self-paced or constant workload exercise in cross-over design studies. Risk of bias was assessed using the Cochrane Risk of Bias Tool for randomized trials. RESULTS Fifty-nine studies (n = 563 athletes) were identified from 3300 records, of which 40 (n = 370 athletes) used a self-paced protocol and 19 (n = 193 athletes) used a constant workload protocol. Eighteen studies compared multiple cooling interventions and were included more than once (total n = 86 experiments and n = 832 paired measurements). Sixty-seven experiments used a pre-cooling intervention and 19 used a per-cooling intervention. Average ambient conditions were 34.0 °C [32.3-35.0 °C] and 50.0% [40.0-55.3%] relative humidity. Cooling interventions attenuated the performance decline in hot conditions and were more effective during a constant workload (effect size [ES] = 0.62, 95% confidence interval [CI] 0.44-0.81) compared with self-paced exercise (ES = 0.30, 95% CI 0.18-0.42, p = 0.004). A difference in performance outcomes between protocols was only observed with pre-cooling (ES = 0.74, 95% CI 0.50-0.98 vs ES = 0.29, 95% CI 0.17-0.42, p = 0.001), but not per-cooling (ES = 0.45, 95% CI 0.16-0.74 vs ES = 0.35, 95% CI 0.01-0.70, p = 0.68). CONCLUSIONS Cooling interventions attenuated the decline in performance during exercise in the heat, but the magnitude of the effect is dependent on exercise protocol (self-paced vs constant workload) and cooling type (pre- vs per-cooling). Pre-cooling appears to be more effective in attenuating the decline in exercise performance during a constant workload compared with self-paced exercise protocols, whereas no differences were found in the effectiveness of per-cooling.
Collapse
Affiliation(s)
- Tessa M van de Kerkhof
- Department of Physiology (392), Radboud University Medical Center, Radboud Institute for Health Sciences, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Coen C W G Bongers
- Department of Physiology (392), Radboud University Medical Center, Radboud Institute for Health Sciences, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
- School of Sports and Exercise, HAN University of Applied Sciences, Nijmegen, The Netherlands
| | - Julien D Périard
- University of Canberra Research Institute for Sport and Exercise, Canberra, ACT, Australia
| | - Thijs M H Eijsvogels
- Department of Physiology (392), Radboud University Medical Center, Radboud Institute for Health Sciences, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
| |
Collapse
|
3
|
Tan SH, Khong TK, Selvanayagam VS, Yusof A. Central effects of mouth rinses on endurance and strength performance. Eur J Appl Physiol 2024; 124:403-415. [PMID: 38038740 DOI: 10.1007/s00421-023-05350-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 10/20/2023] [Indexed: 12/02/2023]
Abstract
Rinsing the mouth with a carbohydrate (CHO) solution has been shown to enhance exercise performance while reducing neuromuscular fatigue. This effect is thought to be mediated through the stimulation of oral receptors, which activate brain areas associated with reward, motivation, and motor control. Consequently, corticomotor responsiveness is increased, leading to sustained levels of neuromuscular activity prior to fatigue. In the context of endurance performance, the evidence regarding the central involvement of mouth rinse (MR) in performance improvement is not conclusive. Peripheral mechanisms should not be disregarded, particularly considering factors such as low exercise volume, the participant's fasting state, and the frequency of rinsing. These factors may influence central activations. On the other hand, for strength-related activities, changes in motor evoked potential (MEP) and electromyography (EMG) have been observed, indicating increased corticospinal responsiveness and neuromuscular drive during isometric and isokinetic contractions in both fresh and fatigued muscles. However, it is important to note that in many studies, MEP data were not normalised, making it difficult to exclude peripheral contributions. Voluntary activation (VA), another central measure, often exhibits a lack of changes, mainly due to its high variability, particularly in fatigued muscles. Based on the evidence, MR can attenuate neuromuscular fatigue and improve endurance and strength performance via similar underlying mechanisms. However, the evidence supporting central contribution is weak due to the lack of neurophysiological measures, inaccurate data treatment (normalisation), limited generalisation between exercise modes, methodological biases (ignoring peripheral contribution), and high measurement variability.Trial registration: PROSPERO ID: CRD42021261714.
Collapse
Affiliation(s)
- Shi Han Tan
- Faculty of Sports and Exercise Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Teng Keen Khong
- Faculty of Sports and Exercise Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Victor S Selvanayagam
- Faculty of Sports and Exercise Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Ashril Yusof
- Faculty of Sports and Exercise Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| |
Collapse
|
4
|
Roriz M, Brito J, Teixeira FJ, Spyrou K, Teixeira VH. The effect of menthol rinsing before intermittent exercise on physiological, physical, and thermo-behavioral responses of male football referees in hot and humid environment. Front Sports Act Living 2024; 6:1334739. [PMID: 38318484 PMCID: PMC10839052 DOI: 10.3389/fspor.2024.1334739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 01/04/2024] [Indexed: 02/07/2024] Open
Abstract
Introduction In the current experiment, we aimed to evaluate whether eliciting pre-exercise non-thermal cooling sensations would alter perceptual measures, and physical and physiological responses in football referees. Methods Nine highly trained male football referees undertook two 45-minute intermittent exercise protocols in hot and humid conditions (34.2 ± 0.6°C, 62.5 ± 1.0% relative humidity). In a randomized counterbalanced crossover design, 1 of 2 beverages were given before the warm-up: a 0.01% menthol solution or a placebo noncaloric solution. Physical performance was quantified as total distance covered in each of the three 15-minute exercise blocks. Core temperature, heart rate, thermal sensation and thermal comfort were measured at rest and after each exercise block. Results No changes were observed between trials and over time for distance covered. No main effect of mouth rinse was observed for core temperature and heart rate, but both increased over time in all conditions (P < 0.001). Thermal sensation and thermal comfort were significantly improved with menthol after mouth-rinsing (P < 0.05), but with no differences at any other time-point. Discussion These results indicate that non-thermal cooling oral stimuli provide immediate behavioral changes but may not influence physiological or physical responses in football referees, during intermittent exercise in hot and humid environments. Clinical Trial Registration www.clinicaltrials.gov, identifier NCT05632692.
Collapse
Affiliation(s)
- Maria Roriz
- Faculty of Nutrition and Food Sciences, University of Porto (FCNAUP), Porto, Portugal
| | - João Brito
- Portugal Football School, Portuguese Football Federation, Oeiras, Portugal
| | - Filipe J. Teixeira
- Interdisciplinary Center for the Study of Human Performance (CIPER), Faculdade de Motricidade Humana, Universidade de Lisboa, Cruz-Quebrada, Portugal
- Atlântica, Instituto Universitário, Fábrica da Pólvora de Barcarena, Barcarena, Portugal
| | - Konstantinos Spyrou
- UCAM Research Center for High Performance Sport, UCAM Universidad Católica de Murcia, Murcia, Spain
- Facultad de Deporte, UCAM Universidad Católica de Murcia, Murcia, Spain
| | - Vitor Hugo Teixeira
- Faculty of Nutrition and Food Sciences, University of Porto (FCNAUP), Porto, Portugal
- Research Centre in Physical Activity, Health and Leisure (CIAFEL), Faculty of Sports, University of Porto (FADEUP), Porto, Portugal
- Laboratory for Integrative and Translational Research in Population Health (ITR), Porto, Portugal
| |
Collapse
|
5
|
Villegas-Serna T, Wilson LJ, Curtis C. Topical application of L-Menthol - Physiological and genetic considerations to assist in developing female athlete research: A narrative review. J Therm Biol 2024; 119:103758. [PMID: 38070272 DOI: 10.1016/j.jtherbio.2023.103758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 11/11/2023] [Accepted: 11/16/2023] [Indexed: 02/25/2024]
Abstract
L-menthol is a cyclic monoterpene derived from aromatic plants, which gives a cooling sensation upon application. With this in mind, L-menthol is beginning to be considered as a potential ergogenic aid for exercise and sporting competitions, particularly in hot environments, however female-specific research is lacking. The aim of this narrative review is to summarize available literature relating to topical application of L-menthol and provide commentary on avenues of consideration relating to future research developments of topical L-menthol in female athletes. From available studies in male participants, L-menthol topical application results in no endurance exercise performance improvements, however decreases in thermal sensation are observed. Mixed results are observed within strength performance parameters. Several genetic variations and single nucleotide polymorphisms have been identified in relation to sweat production, fluid loss and body mass changes - factors which may influence topical application of L-menthol. More specifically to female athletes, genetic variations relating to sweat responses and skin thickness, phases of the menstrual cycle, and body composition indices may affect the ergogenic effects of L-menthol topical application, via alterations in thermogenic responses, along with differing tissue distribution compared to their male counterparts. This narrative review concludes that further development of female athlete research and protocols for topical application of L-menthol is warranted due to physiological and genetic variations. Such developments would benefit research and practitioners alike with further personalized sport science strategies around phases of the menstrual cycle and body composition indices, with a view to optimize ergogenic effects of L-menthol.
Collapse
Affiliation(s)
- Tatiana Villegas-Serna
- Department of Nutrition, Food Science and Physiology, School of Pharmacy and Nutrition, Pamplona, Spain; University of Navarra, Pamplona, Spain
| | - Laura J Wilson
- London Sport Institute, Middlesex University, London, NW4 4BT, United Kingdom
| | - Christopher Curtis
- Department of Nutrition, Food Science and Physiology, School of Pharmacy and Nutrition, Pamplona, Spain; University of Navarra, Pamplona, Spain.
| |
Collapse
|
6
|
Andrade MT, Wanner SP, Santos WME, Mendes TT, Nunes-Leite MMS, de Oliveira GGA, Carmo AAL, Carvalho MV, Silami Garcia E, Soares DD. Ad libitum ice slurry ingestion and half-marathon performance in a hot environment: A study comparing the effects of the amount and moment of ingestion between ice slurry and water at 37 °C. J Therm Biol 2024; 119:103781. [PMID: 38232473 DOI: 10.1016/j.jtherbio.2023.103781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 12/07/2023] [Accepted: 12/21/2023] [Indexed: 01/19/2024]
Abstract
Ice slurry ingestion during prolonged exercises may improve performance in hot environments; however, the ideal amount and timing of ingestion are still uncertain. We determined whether ad libitum ice slurry ingestion influences physiological and perceptual variables and half-marathon performance while comparing the effects of the amount and moment of ingestion between ice slurry and water at 37 °C. Ten trained participants (28 ± 2 years; mean and SD) were required to run two half marathons while consuming either ice slurry (-1 °C; Ad-1) or water (37 °C; 37 CE) ad libitum. They then performed two other half marathons where, during one, they were required to ingest an amount of water equivalent to the amount consumed during the Ad-1 trial (Pro37), and in the other, to ingest ice slurry in the amount consumed during the 37 CE trial (Pro-1). During the half marathons, dry-bulb temperature and relative humidity were controlled at 33.1 ± 0.3 °C and 60 ± 3%, respectively. Ad-1 ingestion (349.6 ± 58.5 g) was 45% less than 37 CE ingestion (635.5 ± 135.8 g). Physical performance, heart rate, perceived exertion, body temperatures, and thermal perception were not influenced by the temperature or amount of beverage ingestion. However, a secondary analysis suggested that lower beverage ingestion was associated with improved performance (Ad-1 + Pro37 vs. 37 CE + Pro-1: -4.0 min, Cohen's d = 0.39), with a significant relationship between lower beverage ingestion and faster running time (b = 0.02, t = 4.01, p < 0.001). In conclusion, ice slurry ingestion does not affect performance or physiological or perceptual variables during a half marathon in a hot environment. Preliminary evidence suggests that lower beverage ingestion (ice slurry or warm water) is associated with improved performance compared to higher ingestion.
Collapse
Affiliation(s)
- Marcelo T Andrade
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, (MG), Brazil; Psychology Program, Belo Horizonte, (MG), Brazil.
| | - Samuel P Wanner
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, (MG), Brazil
| | - Weslley M E Santos
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, (MG), Brazil
| | - Thiago T Mendes
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, (MG), Brazil; Department of Physical Education, Universidade Federal da Bahia, Salvador, (BA), Brazil
| | - Matheus M S Nunes-Leite
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, (MG), Brazil
| | - Gustavo G A de Oliveira
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, (MG), Brazil
| | - Adriano A L Carmo
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, (MG), Brazil
| | - Moisés V Carvalho
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, (MG), Brazil; Department of Human Movement Sciences, Universidade Do Estado de Minas Gerais, Ibirité, (MG), Brazil
| | - Emerson Silami Garcia
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, (MG), Brazil
| | - Danusa D Soares
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, (MG), Brazil
| |
Collapse
|
7
|
Miranda Neto M, Meireles ACF, Alcântara MA, de Magalhães Cordeiro AMT, Silva AS. Peppermint essential oil (Mentha piperita L.) increases time to exhaustion in runners. Eur J Nutr 2023; 62:3411-3422. [PMID: 37665425 DOI: 10.1007/s00394-023-03235-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 08/08/2023] [Indexed: 09/05/2023]
Abstract
PURPOSE This study aimed to evaluate the capacity of peppermint essential oil to improve the physical performance of runners in running protocol until exhaustion. METHODS In a clinical, randomized, double-blind, cross-over and controlled study, fourteen male recreational runners (37.1 ± 2.0 years; 24 ± 1.1 kg/m2; 53.1 ± 1.7 mL kg min) performed two runs to exhaustion at 70% of VO2max, after intake of 500 mL of water added with 0.05 mL of peppermint essential oil (PEO) or placebo (PLA), plus 400 mL of the drink during the initial part of the exercise. Records were made of body temperature (BT), thermal sensation (TS), thermal comfort (TC), subjective perception of effort (SPE), sweat rate (SR), and urine volume and density. RESULTS Time to exhaustion was 109.9 ± 6.9 min in PEO and 98.5 ± 6.2 min in PLA (p = 0.009; effect size: 0.826). No significant changes were observed in the values of BT, TS, TC, SPE, SR, lost body mass, and urine volume and density (p > 0.05). CONCLUSION Peppermint essential oil added to water before and during a race significantly increases the time to exhaustion of recreational runners but without altering BT, TS, TC, or hydration status, so the mechanisms involved were not clarified in this study. BRAZILIAN REGISTRY OF CLINICAL TRIALS (REBEC) RBR-75zt25z.
Collapse
Affiliation(s)
- Manoel Miranda Neto
- Postgraduate Program in Nutrition Sciences, Health Sciences Center, Federal University of Paraíba, Campus I, University City, João Pessoa, Paraíba, 58059-900, Brazil
| | - Ana Carolina Freitas Meireles
- Laboratory of Physical Training Studies Applied to Performance and Health, Federal University of Paraíba, João Pessoa, Paraíba, Brazil
| | - Maristela Alves Alcântara
- Food Technology Department, Center for Technology and Regional Development, Federal University of Paraíba, Campus I, João Pessoa, Paraíba, Brazil
| | | | - Alexandre Sérgio Silva
- Postgraduate Program in Nutrition Sciences, Health Sciences Center, Federal University of Paraíba, Campus I, University City, João Pessoa, Paraíba, 58059-900, Brazil.
- Associate Postgraduate Program in Physical Education, University of Pernambuco/Federal University of Paraíba, João Pessoa, Paraíba, Brazil.
| |
Collapse
|
8
|
Gopathi P, Tiwari KH, Kalpana K. The Effects of Pre-Exercise Ice-Slurry Ingestion on Thermoregulation and Exercise Performance of Highly Trained Athletes: A Scoping Review. INTERNATIONAL JOURNAL OF EXERCISE SCIENCE 2023; 16:1398-1412. [PMID: 38288403 PMCID: PMC10824289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/31/2024]
Abstract
Ice-slurry prepared from plain ice, crushed ice, or sports drink has been used as a cooling strategy before exercise to regulate body temperature and improve exercise performance. However, consensus regarding the benefit is unclear. Therefore, the present review aimed to study the effects of pre-exercise ice-slurry ingestion on thermoregulation and exercise performance of highly trained athletes. The Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) checklist was used. The data extraction was done using the search engine Google Scholar, and digital repositories such as Cochrane, Scopus, Medline, Ebsco, Proquest and Pubmed. The keywords 'Pre-cooling', 'Ice-slurry', 'Ice Slush' 'Thermoregulation' 'Heat Loss' 'Heat Stress' 'Body Temperature' 'Athletes', 'Sports Persons' 'Exercise Performance' were used. Among the identified records (n = 151), 11 articles which met the inclusion criteria were examined. Out of the eleven studies, six studies reported a significant decrease in core/rectal/GI/skin/body temperature, and six studies reported a significant increase, or positive influence on exercise performance, and three studies both on thermoregulation and exercise performance. Ingestion of pre-exercise ice-slurry (30 min BE; -1°C to +1°C) in the dosage range of 7-14g/kg/BM has a significant beneficial effect on thermoregulation and exercise performance. Ice-slurry prepared from plain crushed ice, or sports drink, or carbohydrate and electrolyte drinks may have a similar effect on thermoregulation and exercise performance.
Collapse
Affiliation(s)
- Pranitha Gopathi
- MYAS-NIN Dept. of Sports Science, ICMR-National Institute of Nutrition India
| | | | - Kommi Kalpana
- Dept. of Nutrition and Dietetics, School of Allied Health Sciences, Manav Rachna International Institute of Research and Studies, Delhi-NCR, India
| |
Collapse
|
9
|
ALKEMADE PUCK, EIJSVOGELS THIJSMH, JANSSEN THOMASWJ, JANSEN KASPARMB, KINGMA BORISRM, DAANEN HEINAM. Upper-Body versus Lower-Body Cooling in Individuals with Paraplegia during Arm-Crank Exercise in the Heat. Med Sci Sports Exerc 2023; 55:2014-2024. [PMID: 37418241 PMCID: PMC10581408 DOI: 10.1249/mss.0000000000003244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/08/2023]
Abstract
PURPOSE For wheelchair users with a spinal cord injury, the lower body may be a more convenient cooling site than the upper body. However, it remains unknown if leg cooling reduces thermal strain in these individuals. We compared the impact of upper-body versus lower-body cooling on physiological and perceptual outcomes during submaximal arm-crank exercise under heat stress in individuals with paraplegia. METHODS Twelve male participants with paraplegia (T4-L2, 50% complete lesion) performed a maximal exercise test in temperate conditions, and three heat stress tests (32°C, 40% relative humidity) in which they received upper-body cooling (COOL-UB), lower-body cooling (COOL-LB), or no cooling (CON) in a randomized counterbalanced order. Each heat stress test consisted of four exercise blocks of 15 min at 50% of peak power output, with 3 min of rest in between. Cooling was applied using water-perfused pads, with 14.8-m tubing in both COOL-UB and COOL-LB. RESULTS Gastrointestinal temperature was 0.2°C (95% confidence interval (CI), 0.1°C to 0.3°C) lower during exercise in COOL-UB versus CON (37.5°C ± 0.4°C vs 37.7°C ± 0.3°C, P = 0.009), with no difference between COOL-LB and CON ( P = 1.0). Heart rate was lower in both COOL-UB (-7 bpm; 95% CI, -11 to -3 bpm; P = 0.01) and COOL-LB (-5 bpm; 95% CI, -9 to -1 bpm; P = 0.049) compared with CON. The skin temperature reduction at the cooled skin sites was larger in COOL-LB (-10.8°C ± 1.1°C) than in COOL-UB (-6.7°C ± 1.4°C, P < 0.001), which limited the cooling capacity in COOL-LB. Thermal sensation of the cooled skin sites was improved and overall thermal discomfort was lower in COOL-UB ( P = 0.01 and P = 0.04) but not in COOL-LB ( P = 0.17 and P = 0.59) compared with CON. CONCLUSIONS Upper-body cooling more effectively reduced thermal strain than lower-body cooling in individuals with paraplegia, as it induced greater thermophysiological and perceptual benefits.
Collapse
Affiliation(s)
- PUCK ALKEMADE
- Faculty of Behavioral and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, THE NETHERLANDS
| | - THIJS M. H. EIJSVOGELS
- Radboud Institute for Health Sciences, Department of Physiology, Radboud University Medical Center, Nijmegen, THE NETHERLANDS
| | - THOMAS W. J. JANSSEN
- Faculty of Behavioral and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, THE NETHERLANDS
- Amsterdam Institute of Sport Science, Amsterdam, THE NETHERLANDS
| | - KASPAR M. B. JANSEN
- Department of Design Engineering, Delft University of Technology, Delft, THE NETHERLANDS
| | - BORIS R. M. KINGMA
- Department Human Performance, Unit Defence, Safety and Security, TNO, The Netherlands Organization for Applied Sciences, Soesterberg, THE NETHERLANDS
| | - HEIN A. M. DAANEN
- Faculty of Behavioral and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, THE NETHERLANDS
- Amsterdam Institute of Sport Science, Amsterdam, THE NETHERLANDS
| |
Collapse
|
10
|
Peel J, John K, Page J, Jeffries O, Heffernan SM, Tallent J, Waldron M. Topical application of isolated menthol and combined menthol-capsaicin creams: Exercise tolerance, thermal perception, pain, attentional focus and thermoregulation in the heat. Eur J Sport Sci 2023; 23:2038-2048. [PMID: 37161852 DOI: 10.1080/17461391.2023.2211966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We determined the effects of topically applied (i) isolated menthol cream, (ii) menthol and capsaicin co-application or (iii) placebo cream on exercise tolerance, thermal perception, pain, attentional focus and thermoregulation during exercise in the heat. Ten participants cycled at 70% maximal power output until exhaustion in 35°C and 20% relative humidity after application of (i) 5% isolated menthol, (ii) 5% menthol and 0.025% capsaicin co-application or (iii) placebo cream. Thermo-physiological responses were measured during exercise, with attentional focus and pain determined post-exercise on a 0-to-10 scale. Across the three conditions, time to exhaustion was 13.4 ± 4.8 min, mean ± SD infrared tympanic and skin temperature was 37.2 ± 0.6°C and 35.1 ± 1.2°C, respectively, and heart rate was 152 ± 47 bpm, with no changes between conditions (p > 0.05). Perceived exertion was lower in the isolated menthol vs. all other conditions (p < 0.05, ηp2 = 0.44). Thermal sensation was higher in menthol-capsaicin co-application vs. isolated menthol (p < 0.05, d = 1.1), while sweat rate was higher for capsaicin and menthol co-application compared to menthol (p < 0.05, d = 0.85). The median and interquartile range scores for pain were lower (p < 0.05) in the menthol condition (8, 7-8) compared to both menthol and capsaicin (10, 9-10) and placebo (9, 9-10), which was coupled with a greater distraction (p < 0.05) in the menthol condition (9, 7-10) compared to placebo (6, 5-7). Despite no performance effects for any topical cream application condition, these data reiterate the advantageous perceptual and analgesic role of menthol application and demonstrate no advantage of co-application with capsaicin.HighlightsTopical application of isolated menthol cream to cold-sensitive areas of the body during exhaustive exercise in the heat, elicited reduced perception of pain and enhanced sensation of cooling.While this reduction in generally unpleasant feelings (i.e. pain and heat) were coupled with lower RPE scores in the menthol condition and could be considered beneficial, there was no apparent ergogenic effect in an exercise tolerance test.Co-application of capsaicin and menthol appeared to inhibit the positive sensory effects elicited by menthol.Isolated menthol can induce changes in cognitive processes related to pain and exertion, while also reducing thermal sensation; however, the decision to use menthol creams must be balanced with the limited performance or thermoregulatory effects reported herein during exercise in hot environments.
Collapse
Affiliation(s)
- Jenny Peel
- A-STEM Centre, Faculty of Science & Engineering, Swansea University, Swansea, UK
| | - Kevin John
- A-STEM Centre, Faculty of Science & Engineering, Swansea University, Swansea, UK
| | - Joe Page
- A-STEM Centre, Faculty of Science & Engineering, Swansea University, Swansea, UK
| | - Owen Jeffries
- School of Biomedical, Nutritional and Sport Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - Shane M Heffernan
- A-STEM Centre, Faculty of Science & Engineering, Swansea University, Swansea, UK
| | - Jamie Tallent
- School of Sport, Rehabilitation, and Exercise Sciences, University of Essex, Colchester, UK
- Department of Physiotherapy, Faculty of Medicine, Nursing and Health Sciences, School of Primary and Allied Health Care, Monash University, Colchester, Australia
| | - Mark Waldron
- A-STEM Centre, Faculty of Science & Engineering, Swansea University, Swansea, UK
- Welsh Institute of Performance Science, Swansea University, Swansea, UK
- School of Health and Behavioural Sciences, University of the Sunshine Coast, Queensland, Australia
| |
Collapse
|
11
|
Jerram ML, Baker D, Smith TB, Healey P, Taylor L, Black K. A 0.1% L-Menthol Mouth Swill in Elite Male Rugby Players Has Different Effects in Forwards and Backs. Int J Sports Physiol Perform 2023; 18:909-917. [PMID: 36689991 DOI: 10.1123/ijspp.2022-0191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 09/20/2022] [Accepted: 10/26/2022] [Indexed: 01/24/2023]
Abstract
PURPOSE Menthol mouth swills can improve endurance performance in the heat, which is attributed to attenuations in nonthermally derived thermal sensation (TS) and perception of effort. However, research in elite team-sport athletes is absent. Therefore, this study investigated the performance and TS responses to a 0.1% menthol mouth rinse (MR) or placebo (PLA) among elite male rugby union players. METHOD Twenty-seven (15 Forwards and 12 Backs) elite male Super Rugby players completed two 3-minute 15-a-side rugby-specific conditioning blocks, with MR or PLA provided at the start of training (baseline), at the start of each 3-minute block (swill 1 [S1] and swill 2 [S2]), and at the end of training (swill 3 [S3]). TS was assessed using the American Society of Heating, Refrigerating and Air-Conditioning Engineers 9-point Analog Sensation Scale after each swill and at baseline (preconditioning block). Acceptability was measured after baseline swill and S3 using a 5-question Likert scale. Physical performance was measured throughout training using global positioning system metrics. RESULTS MR attenuated TS from baseline to S1 (P = .003, SD = 1.01) and S2 (P = .002, SD = 1.09) in Forwards only, compared with PLA. Acceptability was higher only for Forwards in MR versus PLA at baseline (P = .003, SD = 1.3) and S3 (P = .004, SD = 0.75). MR had no effect on physical performance metrics (P > .05). CONCLUSION MR attenuated the rise in TS with higher acceptability at S1 and S3 (in Forwards only) with no effect on selected physical performance metrics. Longer-duration exercise (eg, a match) in hot-humid conditions eliciting markedly increased body temperatures could theoretically allow favorable changes in TS to enhance performance-these postulations warrant experimental investigation.
Collapse
Affiliation(s)
- Marcia L Jerram
- Department of Human Nutrition, University of Otago, Dunedin,New Zealand
| | - Dane Baker
- Department of Human Nutrition, University of Otago, Dunedin,New Zealand
| | | | - Phil Healey
- Blues Super Rugby Franchise, Auckland,New Zealand
| | - Lee Taylor
- School of Sport, Exercise and Health Sciences, National Centre for Sport and Exercise Medicine (NCSEM), Loughborough University, Loughborough,United Kingdom
- Human Performance Research Centre, University of Technology Sydney (UTS), Sydney, NSW,Australia
- Sport & Exercise Discipline Group, Faculty of Health, University of Technology Sydney (UTS), Sydney, NSW,Australia
| | - Katherine Black
- Department of Human Nutrition, University of Otago, Dunedin,New Zealand
| |
Collapse
|
12
|
Tsutsumi Y, Momma H, Ebihara S, Nagatomi R. L-menthol administration facilitates breathing comfort during exhaustive endurance running and improves running capacity in well-trained runners: A randomized crossover study. Eur J Sport Sci 2023; 23:1913-1921. [PMID: 35997234 DOI: 10.1080/17461391.2022.2115404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
ABSTRACTThis study aimed to clarify the contribution of L-menthol administration to endurande exercise capacity. Thirteen male runners (age, 35.8 ± 7.8 years; peak oxygen uptake, 62.7 ± 6.8 mL kg-1 min-1) ran on treadmills at fixed intensities of their anaerobic thresholds to exhaustion. All participants underwent three trials-water ingestion (W-IG), L-menthol mouth rinsing (M-MR), and L-menthol ingestion (M-IG)- in a random order every 5 min while running. Breathing comfort (BC) was measured immediately after fluid intake. Dyspnea threshold against external inspiratory resistance was examined before and after the running test. The running time with M-IG (1683.9 ± 520.3 s) was longer than that with W-IG (1410.2 ± 465.9 s, effect size [ES] = 0.55). BC with M-IG (2.00 ± 0.74) was higher than that with W-IG (0.42 ± 0.79) at exhaustion (ES > 2.00). The dyspnea threshold after running decreased to 19.2 ± 7.6 cm H₂O L-1 s-1 with W-IG, whereas that with M-MR (26.2 ± 6.5 cm H₂O L-1 s-1) and M-IG (29.2 ± 2.8 cm H₂O L-1 s-1) remained high (p for interaction < 0.001). M-IG facilitated BC during running, improved endurance capacity, and prevented decreases in the dyspnea threshold against external inspiratory resistance after exhaustive running.HighlightsL-menthol ingestion facilitated breathing comfort during high intensity endurance running and improved exhaustive endurance running capacity.Even after exhaustion, L-menthol solution relieved dyspnea sensitivity against external inspiratory resistance.L-menthol ingestion might help athletes improve their endurance running capacity.
Collapse
Affiliation(s)
- Yoshiko Tsutsumi
- Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Haruki Momma
- Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Satoru Ebihara
- Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Ryoichi Nagatomi
- Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
- Tohoku University Graduate School of Biomedical Engineering, Sendai, Miyagi, Japan
| |
Collapse
|
13
|
Vogel RM, Varone N, Clark C, Ramirez K, Ross MLR, Swann C, Stevens CJ. A Menthol-Enhanced "Cooling" Energy Gel Does Not Influence Laboratory Time Trial Performance in Trained Runners. Nutrients 2023; 15:3379. [PMID: 37571316 PMCID: PMC10420894 DOI: 10.3390/nu15153379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 07/21/2023] [Accepted: 07/25/2023] [Indexed: 08/13/2023] Open
Abstract
l-menthol (menthol) is an organic compound derived from peppermint which imparts a refreshing mint flavor and aroma to oral hygiene products, chewing gum, and topical analgesics. Menthol has been identified as a non-thermal sensory cooling strategy for athletes when ingested or mouth-rinsed during exercise in hot environments. Therefore, sports nutrition products delivering a controlled concentration of menthol could be beneficial for athletes exercising in the heat. We sought to test the performance and perceptual outcomes of a novel menthol energy gel during treadmill running in the heat (33 °C, 49% RH). Fourteen trained runners (mean ± SD; age: 31 ± 6 years, VO2max: 56.5 ± 10.1 mL·kg-1·min-1, BMI: 23.2 ± 2.4 kg/m2; six female) participated in a randomized, crossover, double-blind, and placebo-controlled study. A menthol-enhanced energy gel (0.5% concentration; MEN) or flavor-matched placebo (PLA) was ingested 5 min before and again at 20 and 40 min of a 40 min treadmill exercise preload at 60% VO2max, followed by a 20 min self-paced time trial. The total distance, vertical distance, perceptual measures (thermal comfort, thermal sensation, rating of perceived exertion, and affect), and cognitive performance via computerized neurocognitive assessment were measured. No difference between 20 min self-paced time trial total distance (MEN: 4.22 ± 0.54 km, PLA: 4.22 ± 0.55 km, p = 0.867), vertical distance (MEN: 49.2 ± 24.6 m, PLA: 44.4 ± 11.4 m, p = 0.516), or any perceptual measures was observed (all p > 0.05). Cognitive performance was not different between the trials (all p > 0.05). These results suggest that a menthol energy gel is not superior to a non-menthol gel in terms of performance or perception during treadmill running in the heat. More research is needed to confirm whether these findings translate to ecologically valid settings, including outdoor exercise in ambient heat and during competition.
Collapse
Affiliation(s)
- Roxanne M. Vogel
- Physical Activity, Sport and Exercise Research (PASER) Theme, Faculty of Health, Southern Cross University, Coffs Harbour, NSW 2450, Australia
- GU Energy Labs, Berkeley, CA 94710, USA
| | - Nicole Varone
- School of Health Promotion & Kinesiology, Texas Woman’s University, Denton, TX 76201, USA (K.R.)
| | - Cayla Clark
- School of Health Promotion & Kinesiology, Texas Woman’s University, Denton, TX 76201, USA (K.R.)
| | - Kyndall Ramirez
- School of Health Promotion & Kinesiology, Texas Woman’s University, Denton, TX 76201, USA (K.R.)
| | | | - Christian Swann
- Physical Activity, Sport and Exercise Research (PASER) Theme, Faculty of Health, Southern Cross University, Coffs Harbour, NSW 2450, Australia
| | - Christopher J. Stevens
- Physical Activity, Sport and Exercise Research (PASER) Theme, Faculty of Health, Southern Cross University, Coffs Harbour, NSW 2450, Australia
| |
Collapse
|
14
|
Alhadad SB, Chua MCY, Lee JKW, Low ICC. The effects of low and normal dose ice slurry ingestion on endurance capacity and intestinal epithelial injury in the heat. J Sci Med Sport 2023:S1440-2440(23)00078-6. [PMID: 37179242 DOI: 10.1016/j.jsams.2023.04.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 04/22/2023] [Accepted: 04/25/2023] [Indexed: 05/15/2023]
Abstract
OBJECTIVES Compare the effects of ice slurry ingestion at low and normal doses on endurance capacity and exertional heat stress-induced gastrointestinal perturbations. DESIGN Randomised, cross-over design. METHODS Twelve physically active males completed four treadmill running trials, ingesting ice slurry (ICE) or ambient drink (AMB) at 2 g·kg-1 (Normal; N) or 1 g·kg-1 (Low; L) doses every 15-min during exercise and 8 g·kg-1 (N) or 4 g·kg-1 (L) pre- and post-exercise. Pre-, during and post-exercise serum intestinal fatty-acid binding protein ([I-FABP]) and lipopolysaccharide ([LPS]) concentrations were determined. RESULTS Pre-exercise gastrointestinal temperature (Tgi) was lower in L + ICE than L + AMB (p < 0.05), N + ICE than N + AMB (p < 0.001) and N + ICE than L + ICE (p < 0.001). Higher rate of Tgi rise (p < 0.05) and lower estimated sweat rate (p < 0.001) were observed in N + ICE than N + AMB. Rate of Tgi rise was similar at low dose (p = 0.113) despite a lower estimated sweat rate in L + ICE than L+AMB (p < 0.01). Time-to-exhaustion was longer in L + ICE than L + AMB (p < 0.05), but similar between N + ICE and N + AMB (p = 0.142) and L + ICE and N + ICE (p = 0.766). [I-FABP] and [LPS] were similar (p > 0.05). CONCLUSIONS L + ICE elicited a lower heat dissipation compensatory effect with similar endurance capacity as N + ICE. Ice slurry conferred no protection against exertional heat stress-induced gastrointestinal perturbations.
Collapse
Affiliation(s)
- Sharifah B Alhadad
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Human Potential Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Melissa C Y Chua
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Jason K W Lee
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Human Potential Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Heat Resilience and Performance Centre, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; The N.1 Institute for Health, National University of Singapore, Singapore; Institute for Digital Medicine, National University of Singapore, Singapore
| | - Ivan C C Low
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Human Potential Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
| |
Collapse
|
15
|
Carbohydrate mouth rinse is no more effective than placebo on running endurance of dehydrated and heat acclimated athletes. Eur J Appl Physiol 2023:10.1007/s00421-023-05170-y. [PMID: 36920510 DOI: 10.1007/s00421-023-05170-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Accepted: 02/27/2023] [Indexed: 03/16/2023]
Abstract
PURPOSE To determine whether carbohydrate mouth rinsing would improve endurance running performance of tropical natives in a warm-humid (30 °C and 70% relative humidity) environment. METHOD Twelve endurance male runners [age 25 ± 3 years; peak aerobic capacity ([Formula: see text]O2peak) 57.6 ± 3.6 mL.kg-1.min-1] completed three time-to-exhaustion (TTE) trials at ~ 70% [Formula: see text]O2peak while swilling 25 ml of a 6% carbohydrate (CHO) or taste-matched placebo (PLA) as well as no mouth rinse performed in the control (CON) trial. RESULTS TTE performance was significantly longer in both CHO and PLA trials when compared with the CON trial (54.7 ± 5.4 and 53.6 ± 5.1 vs. 48.4 ± 3.6 min, respectively; p < 0.001 and p = 0.012, respectively), but was not significantly different between CHO and PLA trials (p = 1.000). The rating of perceived exertion was not different between the CHO and PLA trials, however, was significantly affected when compared to the CON trial (p < 0.001). A similar effect was observed for perceived arousal level between the CHO and PLA trials to the CON trial. Core temperature, mean skin temperature and skin blood flow were not significantly different between the three trials (all p > 0.05). Similarly, plasma lactate and glucose as well as exercise heart rate were not influenced by the trials. CONCLUSIONS The present study demonstrates that mouth rinsing, whether carbohydrate or placebo, provides an ergogenic benefit to running endurance when compared to CON in a heat stress environment. Nevertheless, the results do not support the notion that rinsing a carbohydrate solution provides a greater advantage as previously described among non-heat acclimated individuals within a temperate condition.
Collapse
|
16
|
Heydenreich J, Koehler K, Braun H, Grosshauser M, Heseker H, Koenig D, Lampen A, Mosler S, Niess A, Schek A, Carlsohn A. Effects of internal cooling on physical performance, physiological and perceptional parameters when exercising in the heat: A systematic review with meta-analyses. Front Physiol 2023; 14:1125969. [PMID: 37113693 PMCID: PMC10126464 DOI: 10.3389/fphys.2023.1125969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Accepted: 03/27/2023] [Indexed: 04/29/2023] Open
Abstract
Background: An elevated core temperature (Tcore) increases the risk of performance impairments and heat-related illness. Internal cooling (IC) has the potential to lower Tcore when exercising in the heat. The aim of the review was to systematically analyze the effects of IC on performance, physiological, and perceptional parameters. Methods: A systematic literature search was performed in the PubMed database on 17 December 2021. Intervention studies were included assessing the effects of IC on performance, physiological, or perceptional outcomes. Data extraction and quality assessment were conducted for the included literature. The standardized mean differences (SMD) and 95% Confidence Intervals (CI) were calculated using the inverse-variance method and a random-effects model. Results: 47 intervention studies involving 486 active subjects (13.7% female; mean age 20-42 years) were included in the meta-analysis. IC resulted in significant positive effects on time to exhaustion [SMD (95% CI) 0.40 (0.13; 0.67), p < 0.01]. IC significantly reduced Tcore [-0.19 (22120.34; -0.05), p < 0.05], sweat rate [-0.20 (-0.34; -0.06), p < 0.01], thermal sensation [-0.17 (-0.33; -0.01), p < 0.05], whereas no effects were found on skin temperature, blood lactate, and thermal comfort (p > 0.05). IC resulted in a borderline significant reduction in time trial performance [0.31 (-0.60; -0.02), p = 0.06], heart rate [-0.13 (-0.27; 0.01), p = 0.06], rate of perceived exertion [-0.16 (-0.31; -0.00), p = 0.05] and borderline increased mean power output [0.22 (0.00; 0.44), p = 0.05]. Discussion: IC has the potential to affect endurance performance and selected physiological and perceptional parameters positively. However, its effectiveness depends on the method used and the time point of administration. Future research should confirm the laboratory-based results in the field setting and involve non-endurance activities and female athletes. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42022336623.
Collapse
Affiliation(s)
- Juliane Heydenreich
- Working Group Sports Nutrition of German Nutrition Society, Bonn, Germany
- Institute of Sports Sciences, Johannes Gutenberg-University of Mainz, Mainz, Germany
- *Correspondence: Juliane Heydenreich,
| | - Karsten Koehler
- Working Group Sports Nutrition of German Nutrition Society, Bonn, Germany
- Department of Sport and Health Sciences, Technical University of Munich, Munich, Germany
| | - Hans Braun
- Working Group Sports Nutrition of German Nutrition Society, Bonn, Germany
- Manfred Donike Institute for Doping Analysis, Institute of Biochemistry, German Sport University Cologne, Cologne, Germany
| | - Mareike Grosshauser
- Working Group Sports Nutrition of German Nutrition Society, Bonn, Germany
- Olympic Center Rhineland-Palatinate/Saarland, Saarbrücken, Germany
| | - Helmut Heseker
- Working Group Sports Nutrition of German Nutrition Society, Bonn, Germany
- Institute of Nutrition, Consumption and Health, University of Paderborn, Paderborn, Germany
| | - Daniel Koenig
- Working Group Sports Nutrition of German Nutrition Society, Bonn, Germany
- Division of Sports Medicine, Exercise Physiology and Prevention, Center for Sport Science and University Sports, University of Vienna, Vienna, Austria
| | - Alfonso Lampen
- Working Group Sports Nutrition of German Nutrition Society, Bonn, Germany
- Risk Assessment Strategies, German Federal Institute for Risk Assessment, Berlin, Germany
| | - Stephanie Mosler
- Working Group Sports Nutrition of German Nutrition Society, Bonn, Germany
- Olympic Center Stuttgart, Stuttgart, Germany
| | - Andreas Niess
- Working Group Sports Nutrition of German Nutrition Society, Bonn, Germany
- Department of Sports Medicine, University Hospital Tübingen, Tübingen, Germany
| | - Alexandra Schek
- Working Group Sports Nutrition of German Nutrition Society, Bonn, Germany
- Editorial Team of the Journal Leistungssport, German Olympic Sports Confederation, Frankfurt, Germany
| | - Anja Carlsohn
- Working Group Sports Nutrition of German Nutrition Society, Bonn, Germany
- Department of Nutrition and Home Economics, University of Applied Science Hamburg, Hamburg, Germany
| |
Collapse
|
17
|
Vogel RM, Ross MLR, Swann C, Rothwell JE, Stevens CJ. Athlete perceptions of flavored, menthol-enhanced energy gels ingested prior to endurance exercise in the heat. J Int Soc Sports Nutr 2022; 19:580-592. [DOI: 10.1080/15502783.2022.2117995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- Roxanne M Vogel
- Southern Cross University, Discipline of Sport and Exercise Science, Coffs Harbour, Australia
- GU Energy Labs, Berkeley, CA, USA
| | - Megan LR Ross
- Australian Catholic University, Melbourne, Australia
| | - Christian Swann
- Southern Cross University, Discipline of Sport and Exercise Science, Coffs Harbour, Australia
| | - Jessica E Rothwell
- Athletics Australia, Melbourne, Australia
- Victorian Institute of Sport, Australia
| | - Christopher J Stevens
- Southern Cross University, Discipline of Sport and Exercise Science, Coffs Harbour, Australia
| |
Collapse
|
18
|
Roriz M, Brito P, Teixeira FJ, Brito J, Teixeira VH. Performance effects of internal pre- and per-cooling across different exercise and environmental conditions: A systematic review. Front Nutr 2022; 9:959516. [PMID: 36337635 PMCID: PMC9632747 DOI: 10.3389/fnut.2022.959516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 09/19/2022] [Indexed: 11/13/2022] Open
Abstract
Exercise in a hot and humid environment may endanger athlete's health and affect physical performance. This systematic review aimed to examine whether internal administration of ice, cold beverages or menthol solutions may be beneficial for physical performance when exercising in different environmental conditions and sports backgrounds. A systematic search was performed in PubMed, Web of Science, Scopus and SPORTDiscus databases, from inception to April 2022, to identify studies meeting the following inclusion criteria: healthy male and female physically active individuals or athletes (aged ≥18 years); an intervention consisting in the internal administration (i.e., ingestion or mouth rinse) of ice slush, ice slurry or crushed ice and/or cold beverages and/or menthol solutions before and/or during exercise; a randomized crossover design with a control or placebo condition; the report of at least one physical performance outcome; and to be written in English. Our search retrieved 2,714 articles in total; after selection, 43 studies were considered, including 472 participants, 408 men and 64 women, aged 18-42 years, with a VO2max ranging from 46.2 to 67.2 mL⋅kg-1⋅min-1. Average ambient temperature and relative humidity during the exercise tasks were 32.4 ± 3.5°C (ranging from 22°C to 38°C) and 50.8 ± 13.4% (varying from 20.0% to 80.0%), respectively. Across the 43 studies, 7 exclusively included a menthol solution mouth rinse, 30 exclusively involved ice slurry/ice slush/crushed ice/cold beverages intake, and 6 examined both the effect of thermal and non-thermal internal techniques in the same protocol. Rinsing a menthol solution (0.01%) improved physical performance during continuous endurance exercise in the heat. Conversely, the ingestion of ice or cold beverages did not seem to consistently increase performance, being more likely to improve performance in continuous endurance trials, especially when consumed during exercises. Co-administration of menthol with or within ice beverages seems to exert a synergistic effect by improving physical performance. Even in environmental conditions that are not extreme, internal cooling strategies may have an ergogenic effect. Further studies exploring both intermittent and outdoor exercise protocols, involving elite male and female athletes and performed under not extreme environmental conditions are warranted. Systematic review registration: [https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021268197], identifier [CRD42021268197].
Collapse
Affiliation(s)
- Maria Roriz
- Faculty of Nutrition and Food Sciences, University of Porto (FCNAUP), Porto, Portugal
- Futebol Clube do Porto, Porto, Portugal
| | - Pedro Brito
- Research Center in Sports Sciences, Health Sciences and Human Development, CIDESD, University of Maia, ISMAI, Maia, Portugal
| | - Filipe J. Teixeira
- Interdisciplinary Center for the Study of Human Performance (CIPER), Faculdade de Motricidade Humana, Universidade de Lisboa, Cruz-Quebrada, Portugal
- Atlântica, Instituto Universitário, Fábrica da Pólvora de Barcarena, Barcarena, Portugal
- Bettery Lifelab, Bettery S.A., Lisbon, Portugal
| | - João Brito
- Portugal Football School, Portuguese Football Federation, Oeiras, Portugal
| | - Vitor Hugo Teixeira
- Faculty of Nutrition and Food Sciences, University of Porto (FCNAUP), Porto, Portugal
- Futebol Clube do Porto, Porto, Portugal
- Research Centre in Physical Activity, Health and Leisure (CIAFEL), Faculty of Sports, University of Porto (FADEUP), Porto, Portugal
- Laboratory for Integrative and Translational Research in Population Health (ITR), Porto, Portugal
| |
Collapse
|
19
|
Coudevylle GR, Collado A, Sinnapah S, Hue O, Robin N. Cold Suggestion to Cope with the Negative Impact of Tropical Climate. AMERICAN JOURNAL OF PSYCHOLOGY 2022. [DOI: 10.5406/19398298.135.2.04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Abstract
The thermal discomfort experienced in a tropical environment has negative effects on human performance. Cooling techniques before, during, or immediately after exercise have been extensively reported on in the physiological literature, but psychological techniques for subjective cooling have rarely been explored. The purpose of this experiment was to evaluate whether a cold suggestion would have an effect on environmental perceptions and affect in a tropical climate. Fifty participants were assigned in random order to two experimental sessions in similar hot and humid conditions at a 1-week interval (30°C ± 1.2; 87% rH ± 2): one with a suggestion focused on cold and the other a control session. The main results indicated that the suggestion focused on cold significantly decreased thermal discomfort and perceived heat and reduced the degradation on the Feeling Scale. The cold suggestion used as a per-cooling technique to cope with the negative impact of a tropical climate is discussed.
Collapse
|
20
|
de Camargo R, Vilaça A, Mota GR, Elsangedy HM, Haile L, Sasaki JE. The Influence of L-menthol on Time Trial Running Performance in Recreational Runners. RESEARCH QUARTERLY FOR EXERCISE AND SPORT 2022:1-9. [PMID: 35412444 DOI: 10.1080/02701367.2021.2014049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 11/29/2021] [Indexed: 06/14/2023]
Abstract
Purpose: This study investigated the effects of combined mouth rinse and topical application of L-menthol on perceptual responses and running performance under thermoneutral conditions (22 ± 2°C and 30-60% relative humidity). Methods: Twelve recreational male runners (age: 31.7 ± 3.8 years; age range: 27-39 years) completed a familiarization, a control test (CON) and two maximal 10-km time trials (counterbalanced randomized crossover design) performed in different days with a non-thermal cooling intervention (combined application of a L-menthol mouth rinse and topical L-menthol gel - MEN) or placebo (PLA). Performance and perceptual measures (thermal sensation, thermal comfort, ratings of perceived exertion and affective response) were recorded for every km completed in the 10-km test. Results: Performance time was lower in MEN (P = 0.03) and PLA (P = 0.003) compared to CON, but no differences were found between MEN vs PLA (P = 1.00). All perceptual responses increased over time in all conditions (P < 0.0001), but only the thermal sensation was lower (P = 0.01) in the MEN compared to CON. Conclusion: L-menthol strategies promote fresh sensations and may improve running performance in 10-km time trial in recreational runners, but the performance improvement could mainly be due to a placebo effect.
Collapse
|
21
|
Crosby S, Butcher A, McDonald K, Berger N, Bekker PJ, Best R. Menthol Mouth Rinsing Maintains Relative Power Production during Three-Minute Maximal Cycling Performance in the Heat Compared to Cold Water and Placebo Rinsing. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19063527. [PMID: 35329209 PMCID: PMC8949398 DOI: 10.3390/ijerph19063527] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 03/07/2022] [Accepted: 03/13/2022] [Indexed: 11/16/2022]
Abstract
Previous menthol studies have demonstrated ergogenic effects in endurance-based activity. However, there is a need for research in sports whose physiological requirements exceed maximal aerobic capacity. This study assessed the effects of 0.1% menthol mouth-rinsing upon a modified three-minute maximal test in the heat (33.0 ± 3.0 °C; RH 46.0 ± 5.0%). In a randomised crossover single blind placebo-controlled study, 11 participants completed three modified maximal tests, where each trial included a different mouth rinse: either menthol (MEN), cold water (WAT) or placebo (PLA). Participants were asked to rate their thermal comfort (TC), thermal sensation (TS) and rating of perceived exertion (RPE) throughout the test. Heart rate, core temperature, oxygen uptake (VO2), ventilation (VE) and respiratory exchange ratio (RER) were monitored continuously throughout the test, alongside cycling power variables (W; W/kg). A blood lactate (BLa) level was taken pre- and post- test. Small to moderate effects (Cohen's d and accompanying 90% confidence intervals) between solutions MEN, WAT and PLA were observed towards the end of the test in relation to relative power. Specifically, from 75-105 s between solutions MEN and WAT (ES: 0.795; 90% CI: 0.204 to 1.352) and MEN and PLA (ES: 1.059; 90% CI: 0.412 to 1.666), this continued between MEN and WAT (ES: 0.729; 90% CI: 0.152 to 1.276) and MEN and PLA (ES: 0.791; 90% CI: 0.202 to 1.348) from 105-135 s. Between 135-165 s there was a moderate difference between solutions MEN and WAT (ES: 1.058; 90% CI: 0.411 to 1.665). This indicates participants produced higher relative power for longer durations with the addition of the menthol mouth rinse, compared to cold water or placebo. The use of menthol (0.1%) as a mouth rinse showed small performance benefits for short duration high intensity exercise in the heat.
Collapse
Affiliation(s)
- Seana Crosby
- Centre for Sport Science & Human Performance, Waikato Institute of Technology, Hamilton 3200, New Zealand; (S.C.); (A.B.); (K.M.); (P.J.B.)
| | - Anna Butcher
- Centre for Sport Science & Human Performance, Waikato Institute of Technology, Hamilton 3200, New Zealand; (S.C.); (A.B.); (K.M.); (P.J.B.)
| | - Kerin McDonald
- Centre for Sport Science & Human Performance, Waikato Institute of Technology, Hamilton 3200, New Zealand; (S.C.); (A.B.); (K.M.); (P.J.B.)
| | - Nicolas Berger
- School of Health and Life Sciences, Teesside University, Middlesbrough TS1 3BX, UK;
| | - Petrus J. Bekker
- Centre for Sport Science & Human Performance, Waikato Institute of Technology, Hamilton 3200, New Zealand; (S.C.); (A.B.); (K.M.); (P.J.B.)
| | - Russ Best
- Centre for Sport Science & Human Performance, Waikato Institute of Technology, Hamilton 3200, New Zealand; (S.C.); (A.B.); (K.M.); (P.J.B.)
- Correspondence:
| |
Collapse
|
22
|
Mazalan NS, Landers GJ, Wallman KE, Ecker U. A Combination of Ice Ingestion and Head Cooling Enhances Cognitive Performance during Endurance Exercise in the Heat. J Sports Sci Med 2022; 21:23-32. [PMID: 35250330 PMCID: PMC8851111 DOI: 10.52082/jssm.2022.23] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 10/20/2021] [Indexed: 06/14/2023]
Abstract
This study assessed the effectiveness of head cooling during exercise in the heat on cognitive performance, either alone or with ice ingestion. Ten healthy males, non-acclimatized to heat, ran (70% V̇O2peak) for 2×30 min in heat (35 ± 0.9°C, 68.2 ± 6.9% RH). Participants completed 3 trials: 10 min of head cooling during exercise (HC); precooling with crushed ice (7gikg-1) and head cooling during exercise (MIX); or no-cooling/control (CON). Working memory was assessed using the automated operation span task (OSPAN) and serial seven test (S7). Following MIX, S7 scores were improved compared to CON (12 ± 9.5, p = 0.004, d = 1.42, 0.34-2.28) and HC (4 ± 5.5, p = 0.048, d = 0.45, -0.47 to 1.3) during exercise. Moderate to large effect sizes were recorded for S7 and OSPAN following MIX and HC compared to CON, suggesting a tendency for improved cognitive performance during exercise in heat. Following precooling (MIX), core body temperature (Tc) and forehead temperature (Th) were lower compared to baseline (-0.75 ± 0.37°C, p < 0.001; -0.31 ± 0.29°C, p = 0.008, respectively) but not in HC or CON (p > 0.05). Thermal sensation (TS) was lower in MIX and HC compared to CON during exercise (p < 0.05). The reduction in Tc, Th and TS with MIX may have attenuated the effect of heat and subsequently improved working memory during exercise in heat.
Collapse
Affiliation(s)
- Nur Shakila Mazalan
- School of Human Sciences (Exercise and Sports Science), The University of Western Australia, Crawley, WA, Australia
- Faculty of Education, National University of Malaysia, Bangi, Selangor, Malaysia
| | - Grant Justin Landers
- School of Human Sciences (Exercise and Sports Science), The University of Western Australia, Crawley, WA, Australia
| | - Karen Elizabeth Wallman
- School of Human Sciences (Exercise and Sports Science), The University of Western Australia, Crawley, WA, Australia
| | - Ullrich Ecker
- School of Psychological Science, The University of Western Australia, Crawley, WA, Australia
| |
Collapse
|
23
|
Best R, Crosby S, Berger N, McDonald K. The Effect of Isolated and Combined Application of Menthol and Carbohydrate Mouth Rinses on 40 km Time Trial Performance, Physiological and Perceptual Measures in the Heat. Nutrients 2021; 13:4309. [PMID: 34959861 PMCID: PMC8708984 DOI: 10.3390/nu13124309] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 11/24/2021] [Accepted: 11/28/2021] [Indexed: 01/31/2023] Open
Abstract
The current study compared mouth swills containing carbohydrate (CHO), menthol (MEN) or a combination (BOTH) on 40 km cycling time trial (TT) performance in the heat (32 °C, 40% humidity, 1000 W radiant load) and investigates associated physiological (rectal temperature (Trec), heart rate (HR)) and subjective measures (thermal comfort (TC), thermal sensation (TS), thirst, oral cooling (OC) and RPE (legs and lungs)). Eight recreationally trained male cyclists (32 ± 9 y; height: 180.9 ± 7.0 cm; weight: 76.3 ± 10.4 kg) completed familiarisation and three experimental trials, swilling either MEN, CHO or BOTH at 10 km intervals (5, 15, 25, 35 km). The 40 km TT performance did not differ significantly between conditions (F2,14 = 0.343; p = 0.715; η2 = 0.047), yet post-hoc testing indicated small differences between MEN and CHO (d = 0.225) and MEN and BOTH (d = 0.275). Subjective measures (TC, TS, RPE) were significantly affected by distance but showed no significant differences between solutions. Within-subject analysis found significant interactions between solution and location upon OC intensity (F28,196 = 2.577; p < 0.001; η2 = 0.269). While solutions containing MEN resulted in a greater sensation of OC, solutions containing CHO experienced small improvements in TT performance. Stimulation of central CHO pathways during self-paced cycling TT in the heat may be of more importance to performance than perceptual cooling interventions. However, no detrimental effects are seen when interventions are combined.
Collapse
Affiliation(s)
- Russ Best
- Centre for Sports Science and Human Performance, Waikato Institute of Technology, Hamilton 3200, New Zealand; (S.C.); (K.M.)
| | - Seana Crosby
- Centre for Sports Science and Human Performance, Waikato Institute of Technology, Hamilton 3200, New Zealand; (S.C.); (K.M.)
| | - Nicolas Berger
- School of Health and Life Sciences, Teesside University, Middlesbrough TS1 3BX, UK;
| | - Kerin McDonald
- Centre for Sports Science and Human Performance, Waikato Institute of Technology, Hamilton 3200, New Zealand; (S.C.); (K.M.)
| |
Collapse
|
24
|
Dilution Method of Menthol Solutions Affects Subsequent Perceptual Thermal Responses during Passive Heat Exposure in Non-Heat Acclimated Participants. BEVERAGES 2021. [DOI: 10.3390/beverages7030062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Due to its volatility, the qualitative experience of menthol may be modulated by its preparation and combination with other compounds. One such method of preparation is dilution, with two dilution methods existing within the sport and exercise science literature, where menthol is used to impart feelings of oral cooling and improve thermal comfort and sensation during heat exposure. This study compared these two dilution methods; one using a solvent the other using temperature, via a randomized counterbalanced repeated measures design (n = 12; Height: 174.0 ± 8.5 cm Mass: 73.4 ± 13.3 kg Age: 28.7 ± 8.4 y; two exposures to each solution) to assess the effect of solution and heat exposure, upon thermal comfort, thermal sensation and associated physiological parameters in non-heat acclimated participants. Thermal comfort was significantly affected by solution (p = 0.041; η2 = 0.017) and time (p < 0.001; η2 = 0.228), whereas thermal sensation was significantly affected by time only (p = 0.012; η2 = 0.133), as was tympanic temperature (p < 0.001; η2 = 0.277). Small to moderate clear differences between solutions at matched time points were also observed. These trends and effects suggest that, depending upon the dilution method employed, the resultant perceptual effects are likely impacted; this also likely depends upon the timing of menthol administration within a heat exposure session.
Collapse
|
25
|
Lei TH, Wang F. Looking ahead of 2021 Tokyo Summer Olympic Games: How Does Humid Heat Affect Endurance Performance? Insight into physiological mechanism and heat-related illness prevention strategies. J Therm Biol 2021; 99:102975. [PMID: 34420619 DOI: 10.1016/j.jtherbio.2021.102975] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/15/2021] [Accepted: 04/16/2021] [Indexed: 12/25/2022]
Abstract
The combination of high humidity and ambient temperature of the 2021 Tokyo Summer Olympic Game will undoubtfully result in greater physiological strains and thereby downregulates the endurance performance of athletes. Although many research studies have highlighted that the thermoregulatory strain is greater when the environment is hot and humid, no review articles have addressed the thermoregulatory and performance differences between dry and humid heat and such lack of consensuses in this area will lead to increase the risk of heat-related injuries as well as suboptimal preparation. Furthermore, specific strategies to counteract this stressful environment has not been outlined in the current literature. Therefore, the purposes of this review are: 1) to provide a clear evidence that humid heat is more stressful than dry heat for both male and female athletes and therefore the preparation for the Tokyo Summer Olympic should be environmental specific instead of a one size fits all approach; 2) to highlight why female athletes may be facing a disadvantage when performing a prolonged endurance event under high humidity environment and 3) to highlight the potential interventional strategies to reduce thermal strain in hot-humid environment. The summaries of this review are: both male and female should be aware of the environmental condition in Tokyo as humid heat is more stressful than dry heat; Short-term heat acclimation may not elicit proper thermoregulatory adaptations in hot-humid environment; cold water immersion with proper hydration and some potential per-cooling modalities may be beneficial for both male and female athletes in hot-humid environment.
Collapse
Affiliation(s)
- Tze-Huan Lei
- College of Physical Education, Hubei Normal University, Huangshi, China
| | - Faming Wang
- School of Architecture and Art, Central South University, Changsha, China.
| |
Collapse
|
26
|
Gavel EH, Hawke KV, Bentley DJ, Logan-Sprenger HM. Menthol Mouth Rinsing Is More Than Just a Mouth Wash-Swilling of Menthol to Improve Physiological Performance. Front Nutr 2021; 8:691695. [PMID: 34307438 PMCID: PMC8292615 DOI: 10.3389/fnut.2021.691695] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 06/10/2021] [Indexed: 01/13/2023] Open
Abstract
Interventions that solely act on the central nervous system (CNS) are gaining considerable interest, particularly products consumed through the oral cavity. The oropharyngeal cavity contains a wide array of receptors that respond to sweet, bitter, and cold tastants, all of which have been shown to improve physiological performance. Of late, the ergogenic benefits of carbohydrate (CHO) and caffeine (CAF) mouth rinsings (MRs) have been widely studied; however, less is known about menthol (MEN). That the physiological state and environmental conditions impact the response each product has is increasingly recognized. While the effects of CHO and CAF MRs have been thoroughly studied in both hot and thermoneutral conditions, less is known about MEN as it has only been studied in hot environments. As such, this review summarizes the current knowledge regarding the MEN MR and exercise modality, frequency of the mouth rinse, and mouth rinse duration and compares two different types of study designs: time trials vs. time to exhaustion (TTE).
Collapse
Affiliation(s)
- Erica H Gavel
- Faculty of Science, Ontario Tech University, Oshawa, ON, Canada
| | - Kierstyn V Hawke
- Faculty of Health Science, Ontario Tech University, Oshawa, ON, Canada
| | - David J Bentley
- Faculty of Health Science, Ontario Tech University, Oshawa, ON, Canada
| | - Heather M Logan-Sprenger
- Faculty of Science, Ontario Tech University, Oshawa, ON, Canada.,Faculty of Health Science, Ontario Tech University, Oshawa, ON, Canada.,Canadian Sport Institute Ontario, Toronto, ON, Canada
| |
Collapse
|
27
|
Périard JD, Eijsvogels TMH, Daanen HAM. Exercise under heat stress: thermoregulation, hydration, performance implications, and mitigation strategies. Physiol Rev 2021; 101:1873-1979. [PMID: 33829868 DOI: 10.1152/physrev.00038.2020] [Citation(s) in RCA: 124] [Impact Index Per Article: 41.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
A rise in body core temperature and loss of body water via sweating are natural consequences of prolonged exercise in the heat. This review provides a comprehensive and integrative overview of how the human body responds to exercise under heat stress and the countermeasures that can be adopted to enhance aerobic performance under such environmental conditions. The fundamental concepts and physiological processes associated with thermoregulation and fluid balance are initially described, followed by a summary of methods to determine thermal strain and hydration status. An outline is provided on how exercise-heat stress disrupts these homeostatic processes, leading to hyperthermia, hypohydration, sodium disturbances, and in some cases exertional heat illness. The impact of heat stress on human performance is also examined, including the underlying physiological mechanisms that mediate the impairment of exercise performance. Similarly, the influence of hydration status on performance in the heat and how systemic and peripheral hemodynamic adjustments contribute to fatigue development is elucidated. This review also discusses strategies to mitigate the effects of hyperthermia and hypohydration on exercise performance in the heat by examining the benefits of heat acclimation, cooling strategies, and hyperhydration. Finally, contemporary controversies are summarized and future research directions are provided.
Collapse
Affiliation(s)
- Julien D Périard
- University of Canberra Research Institute for Sport and Exercise, Bruce, Australia
| | - Thijs M H Eijsvogels
- Department of Physiology, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Hein A M Daanen
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| |
Collapse
|
28
|
Menthol Mouth Rinsing and Cycling Performance in Females Under Heat Stress. Int J Sports Physiol Perform 2021; 16:1014-1020. [PMID: 33662928 DOI: 10.1123/ijspp.2020-0414] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 08/05/2020] [Accepted: 08/06/2020] [Indexed: 11/18/2022]
Abstract
PURPOSE The effects of menthol (MEN) mouth rinse (MR) on performance, physiological, and perceptual variables in female cyclists during a 30-km independent time trial (ITT) were tested. METHODS The participants (n = 9) cycled for 30 km in hot conditions (30°C [0.6°C], 70% [1%] relative humidity, 12 [1] km/h wind speed) on 2 test occasions: with a placebo MR and with MEN MR. Handgrip and a 5-second sprint were measured before, following the first MR, and after the ITT. Ratings of perceived exertion Borg 6 to 20, thermal sensation, and thermal pleasantness were recorded every 5 km. Core temperature and heart rate were recorded throughout. RESULTS The ITT performance significantly improved with MEN MR by 2.3% (2.7%) relative to the placebo (62.6 [5.7] vs 64.0 [4.9] min P = .034; d = 0.85; 95% confidence interval, 0.14 to 2.8 min). The average power output was significantly higher in the MEN trial (P = .031; d = 0.87; 95% confidence interval, 0.9 to 15.0 W). No significant interaction of time and MR for handgrip (P = .581, η2 = .04) or sprint was observed (P = .365, η2 = .103). Core temperature, heart rate, ratings of perceived exertion, and thermal sensation did not significantly differ between trials at set distances (P > .05). Pleasantness significantly differed between the placebo and MEN only at 5 km, with no differences at other TT distances. CONCLUSION These results suggest that a nonthermal cooling agent can improve 30-km ITT performance in female cyclists, although the improved performance with MEN MR is not due to altered thermal perception.
Collapse
|
29
|
Waldock KAM, Hayes M, Watt PW, Maxwell NS. The elderly's physiological and perceptual responses to cooling during simulated activities of daily living in UK summer climatic conditions. Public Health 2021; 193:1-9. [PMID: 33662760 DOI: 10.1016/j.puhe.2021.01.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 12/16/2020] [Accepted: 01/14/2021] [Indexed: 01/10/2023]
Abstract
OBJECTIVES The elderly are the most at-risk population for heat-related illness and mortality during the periods of hot weather. However, evidence-based elderly-specific cooling strategies to prevent heat-illness are limited. The aim of this investigation was to quantify the elderly's physiological and perceptual responses to cooling through cold water ingestion (COLD) or an L-menthol mouth rinse (MENT) during simulated activities of daily living in UK summer climatic conditions. STUDY DESIGN Randomised, controlled repeated measures research design. METHODS A total of ten participants (men n = 7, women n = 3: age; 69 ± 3 yrs, height; 168 ± 10 cm, body mass; 68.88 ± 13.72 kg) completed one preliminary and three experimental trials; control (CON), COLD and MENT. Experimental trials consisted of 40 min rest followed by 30 min of cycling exercise at 6 metabolic equivalents and a 6-min walk test (6MWT), within a 35 °C, 50% relative humidity environment. Experimental interventions (every 10 min); cold water (4 °C) ingestion (total of 1.5L) or menthol (5 ml mouth swill for 5 s, menthol concentration of 0.01%). RESULTS Peak rectal temperature (Tre) was significantly (P < 0.05) lower in COLD compared with CON (-0.34 ± 0.16 °C) and MENT (-0.36 ± 0.20 °C). End exercise heart rate (HR) decreased in COLD compared with CON (-7 ± 9 b min-1) and MENT (-6 ± 7 b min-1). There was no difference in end exercise thermal sensation (TS) (CON; 6.1 ± 0.4, COLD; 6.0 ± 0.4, MENT; 6.4 ± 0.6) or thermal comfort (TC) (CON; 4 ± 1, COLD; 4 ± 1, MENT; 4 ± 1) between trials. The participants walked significantly further during the COLD 6MWT compared with CON (40 m ± 40 m) and MENT (40 m ± 30 m). There was reduced physiological strain in the COLD 6MWT compared with CON (Tre; -0.21 ± 0.24 °C, HR; -7 ± 8 b min-1) and MENT (Tre; -0.23 ± 0.24 °C, HR; -4 ± 7 b min-1). CONCLUSION The elderly have reduced physiological strain (Tre and HR) during activities of daily living and a 6MWT in hot UK climatic conditions, when they drink cold water. Furthermore, the elderly's perception (TS and TC) of the hot environment did not differ from CON at the end of exercise with COLD or MENT interventions. Menthol provided neither perceptual benefit to exercise in the heat nor functional gain. The TS data indicate that elderly may be at increased risk of heat illness, due to not feeling hot and uncomfortable enough to implement physiological strain reducing strategies such as cold-water ingestion.
Collapse
Affiliation(s)
- K A M Waldock
- Army Health and Performance Research, Andover, United Kingdom; Environmental Extremes Laboratory, University of Brighton, Eastbourne, United Kingdom.
| | - M Hayes
- Environmental Extremes Laboratory, University of Brighton, Eastbourne, United Kingdom
| | - P W Watt
- Environmental Extremes Laboratory, University of Brighton, Eastbourne, United Kingdom
| | - N S Maxwell
- Environmental Extremes Laboratory, University of Brighton, Eastbourne, United Kingdom
| |
Collapse
|
30
|
Racinais S, Ihsan M, Taylor L, Cardinale M, Adami PE, Alonso JM, Bouscaren N, Buitrago S, Esh CJ, Gomez-Ezeiza J, Garrandes F, Havenith G, Labidi M, Lange G, Lloyd A, Moussay S, Mtibaa K, Townsend N, Wilson MG, Bermon S. Hydration and cooling in elite athletes: relationship with performance, body mass loss and body temperatures during the Doha 2019 IAAF World Athletics Championships. Br J Sports Med 2021; 55:1335-1341. [PMID: 33579722 PMCID: PMC8606454 DOI: 10.1136/bjsports-2020-103613] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/04/2021] [Indexed: 11/09/2022]
Abstract
Purpose To characterise hydration, cooling, body mass loss, and core (Tcore) and skin (Tsk) temperatures during World Athletics Championships in hot-humid conditions. Methods Marathon and race-walk (20 km and 50 km) athletes (n=83, 36 women) completed a pre-race questionnaire. Pre-race and post-race body weight (n=74), Tcore (n=56) and Tsk (n=49; thermography) were measured. Results Most athletes (93%) had a pre-planned drinking strategy (electrolytes (83%), carbohydrates (81%)) while ice slurry was less common (11%; p<0.001). More men than women relied on electrolytes and carbohydrates (91%–93% vs 67%–72%, p≤0.029). Drinking strategies were based on personal experience (91%) rather than external sources (p<0.001). Most athletes (80%) planned pre-cooling (ice vests (53%), cold towels (45%), neck collars (21%) and ice slurry (21%)) and/or mid-cooling (93%; head/face dousing (65%) and cold water ingestion (52%)). Menthol usage was negligible (1%–2%). Pre-race Tcore was lower in athletes using ice vests (37.5°C±0.4°C vs 37.8°C±0.3°C, p=0.024). Tcore (pre-race 37.7°C±0.3°C, post-race 39.6°C±0.6°C) was independent of event, ranking or performance (p≥0.225). Pre-race Tsk was correlated with faster race completion (r=0.32, p=0.046) and was higher in non-finishers (did not finish (DNF); 33.8°C±0.9°C vs 32.6°C±1.4°C, p=0.017). Body mass loss was higher in men than women (−2.8±1.5% vs −1.3±1.6%, p<0.001), although not associated with performance. Conclusion Most athletes’ hydration strategies were pre-planned based on personal experience. Ice vests were the most adopted pre-cooling strategy and the only one minimising Tcore, suggesting that event organisers should be cognisant of logistics (ie, freezers). Dehydration was moderate and unrelated to performance. Pre-race Tsk was related to performance and DNF, suggesting that Tsk modulation should be incorporated into pre-race strategies.
Collapse
Affiliation(s)
- Sebastien Racinais
- Research and Scientific Support, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Ad Dawhah, Qatar
| | - Mohammed Ihsan
- Research and Scientific Support, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Ad Dawhah, Qatar
- Human Potential Translational Research Program, NUS Yong Loo Lin School of Medicine, Singapore
| | - Lee Taylor
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
- Human Performance Research Centre, University of Technology Sydney, Sydney, New South Wales, Australia
| | - Marco Cardinale
- Research and Scientific Support, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Ad Dawhah, Qatar
- Institute of Sport Exercise and Health (ISEH), University College London, London, UK
| | | | - Juan Manuel Alonso
- Sports Medicine, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Ad Dawhah, Qatar
| | | | | | - Chris J Esh
- Research and Scientific Support, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Ad Dawhah, Qatar
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Josu Gomez-Ezeiza
- Institute of Sport and Exercise Medicine, Stellenbosch University Faculty of Medicine and Health Sciences, Cape Town, Western Cape, South Africa
| | | | - George Havenith
- Environmental Ergonomics Research Centre, Loughborough University, Loughborough, Leics, UK
| | - Mariem Labidi
- Research and Scientific Support, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Ad Dawhah, Qatar
| | - Gunter Lange
- Health and Science Department, World Athletics, Monaco
| | - Alexander Lloyd
- Environmental Ergonomics Research Centre, Loughborough University, Loughborough, Leics, UK
| | - Sebastien Moussay
- Normandie Univ, UNICAEN, INSERM, COMETE, CYCERON, CHU Caen, Caen, Normandie, France
| | - Khouloud Mtibaa
- Physical Education Department, College of Education, Qatar University, Doha, Qatar
| | - Nathan Townsend
- Research and Scientific Support, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Ad Dawhah, Qatar
- College of Health and Life Sciences, Hamad Bin Khalifa University, Doha, Ad Dawhah, Qatar
| | - Mathew G Wilson
- Research and Scientific Support, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Ad Dawhah, Qatar
- Institute of Sport Exercise and Health (ISEH), University College London, London, UK
| | - Stephane Bermon
- Health and Science Department, World Athletics, Monaco
- Human Motricity Laboratory Expertise Sport Health, Cote d'Azur University, Nice, Provence-Alpes-Côte d'Azu, France
| |
Collapse
|
31
|
Perceptual and Physiological Responses to Carbohydrate and Menthol Mouth-Swilling Solutions: A Repeated Measures Cross-Over Preliminary Trial. BEVERAGES 2021. [DOI: 10.3390/beverages7010009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Carbohydrate and menthol mouth-swilling have been used to enhance exercise performance in the heat. However, these strategies differ in mechanism and subjective experience. Participants (n = 12) sat for 60 min in hot conditions (35 °C; 15 ± 2%) following a 15 min control period, during which the participants undertook three 15 min testing blocks. A randomised swill (carbohydrate; menthol; water) was administered per testing block (one swill every three minutes within each block). Heart rate, tympanic temperature, thermal comfort, thermal sensation and thirst were recorded every three minutes. Data were analysed by ANOVA, with carbohydrate intake controlled for via ANCOVA. Small elevations in heart rate were observed after carbohydrate (ES: 0.22 ± 90% CI: −0.09–0.52) and water swilling (0.26; −0.04–0.54). Menthol showed small improvements in thermal comfort relative to carbohydrate (−0.33; −0.63–0.03) and water (−0.40; from −0.70 to −0.10), and induced moderate reductions in thermal sensation (−0.71; from −1.01 to −0.40 and −0.66; from −0.97 to −0.35, respectively). Menthol reduced thirst by a small to moderate extent. These effects persisted when controlling for dietary carbohydrate intake. Carbohydrate and water may elevate heart rate, whereas menthol elicits small improvements in thermal comfort, moderately improves thermal sensation and may mitigate thirst; these effects persist when dietary carbohydrate intake is controlled for.
Collapse
|
32
|
Ashworth ET, Cotter JD, Kilding AE. Impact of elevated core temperature on cognition in hot environments within a military context. Eur J Appl Physiol 2021; 121:1061-1071. [PMID: 33426575 PMCID: PMC7797274 DOI: 10.1007/s00421-020-04591-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 12/17/2020] [Indexed: 01/31/2023]
Abstract
PURPOSE Cognition can be impaired during exercise in the heat, potentially contributing to military casualties. To our knowledge, the independent role of elevated core temperature during exercise has not been determined. The aim of the current study was to evaluate effects of elevated core temperature on cognition during physically encumbering, heated exercise, and to determine whether the perceptual cooling effects of menthol preserves cognition. METHODS Eight participants complete three trials in randomised order: one normothermic (CON) and two with elevated (38.5°C) core temperature, induced by prior immersion in neutral versus hot water The CON trial and one hot trial (HOT) used a water mouth-rinse following each cognitive task of the trial, (HOT) while the other used a menthol mouth-rinse (MENT). Participants walked in humid heat (33°C, 75% relative humidity) in military clothing, completing a cognitive battery of reaction time, perceptual processing, working memory, executive function, cognitive flexibility, vigilance, and declarative memory. RESULTS No differences in cognitive performance were observed between any conditions. Near-infrared spectroscopy showed greater oxygenated haemoglobin tissue content in HOT and MENT compared to CON (ΔO2Hb-deO2Hb: 2.3 ± 4.5 µM, p < .024), and lower deoxygenated haemoglobin in MENT than in CON or HOT (p = .017), suggesting higher brain metabolism during the more stressful conditions. CONCLUSION Moderately elevated core (38.5°C) and skin temperature does not appear to impair cognitive performance during exercise despite mildly elevated cerebral metabolism. The effects of menthol remain undetermined due to the lack of heat-mediated cognitive impairment.
Collapse
Affiliation(s)
- Edward Tom Ashworth
- Sports Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, 17 Antares Place, Rosedale, Auckland, 0632, New Zealand.
| | - James David Cotter
- School of Physical Education, Sport and Exercise Sciences, University of Otago, 55/47 Union Street W, North Dunedin, Dunedin, 9016, New Zealand
| | - Andrew Edward Kilding
- Sports Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, 17 Antares Place, Rosedale, Auckland, 0632, New Zealand
| |
Collapse
|
33
|
Development of a "Cooling" Menthol Energy Gel for Endurance Athletes: Effect of Menthol Concentration on Acceptability and Preferences. Int J Sport Nutr Exerc Metab 2021; 31:40-45. [PMID: 33248439 DOI: 10.1123/ijsnem.2020-0190] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 09/18/2020] [Accepted: 09/21/2020] [Indexed: 11/18/2022]
Abstract
Menthol is effective at stimulating thermosensitive neurons that evoke pleasant cooling sensations. Internal application of menthol can be ergogenic for athletes, and hence, addition of menthol to sports nutrition products may be beneficial for athletes. The aim of this study was to develop a menthol energy gel for consumption during exercise and to determine acceptability and preferences for gels with different menthol concentrations. With a randomized, crossover, and double-blind placebo-controlled design, 40 endurance athletes (20 females) ingested an energy gel with a menthol additive at a high (0.5%; HIGH) or low concentration (0.1%; LOW), or a mint-flavored placebo (CON), on separate occasions during outdoor endurance training sessions. The athletes rated the gels for cooling sensation, mint flavor intensity, sweetness, and overall experience and provided feedback. Results are reported as median (interquartile range). Both menthol gels successfully delivered a cooling sensation, with a significantly greater response for HIGH (5.0 [4.0-5.0]) compared with LOW (3.5 [3.0-4.0]; p = .022) and CON (1.0 [1.0-2.0]; p < .0005), and LOW compared with CON (p < .0005). Ratings of mint flavor intensity followed the same trend as cooling sensation, while ratings of overall experience were significantly worse for HIGH (2.0 [1.0-3.0]) compared with LOW (4.0 [2.0-4.0]; p = .001) and CON (4.0 [3.0-4.0]; p < .0005). An energy gel with the addition of menthol at 0.1-0.5% provides a cooling sensation for athletes with a dose-response when ingested during exercise. The 0.1% concentration is recommended to maximize the overall experience of the gel.
Collapse
|
34
|
Parton AJ, Waldron M, Clifford T, Jeffries O. Thermo-behavioural responses to orally applied l-menthol exhibit sex-specific differences during exercise in a hot environment. Physiol Behav 2020; 229:113250. [PMID: 33220326 DOI: 10.1016/j.physbeh.2020.113250] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 09/29/2020] [Accepted: 11/16/2020] [Indexed: 10/23/2022]
Abstract
AIMS This study investigated the efficacy of l-menthol mouth-rinsing on thermal sensation and perceived effort in females and males, using a fixed-rating of perceived exertion (RPE) exercise protocol in a hot environment. METHODS Twenty-two participants (eleven females, eleven males) completed two trials using a fixed-RPE protocol at an exercise intensity between 'hard' and 'very hard', equating to 16 on the RPE scale at ~35 °C. Participants adjusted power output to maintain RPE-16. In a randomised, double-blind, crossover design, l-menthol or a control mouthwash was administered at an orally neutral temperature (~32 °C) prior to exercise and at 10 min intervals thereafter. Measures of mechanical power output, core temperature, heart rate, perception of thermal sensation and thermal comfort, and whole-body sweat loss are reported. RESULTS Thermal sensation was lowered by l-menthol in both sexes (P < 0.05), however during exercise this was only maintained for 40% of the trial duration in females. Thermal comfort did not differ between conditions (P > 0.05). No differences in exercise duration were observed compared to control, despite a ~4% and ~6% increase in male and females respectively. Power output increased by ~6.5% males (P = 0.039) with no difference in females ~2.2% (P = 0.475), compared to control. Core temperature, heart rate and whole-body sweat loss was not different between condition or sex. CONCLUSIONS l-menthol lowered perceptual measures of thermal sensation in females, but did not attenuate a greater rate of rise in thermal sensitivity when exercising in a hot environment, compared to males. Males appeared to adopt a higher risk strategy by increasing power output following l-menthol administration in contrast to a more conservative pacing strategy in females. Therefore, there appear to be sex-specific differences in l-menthol's non-thermal cooling properties and subsequent effects on thermo-behavioural adjustments in work-load when exercising in a hot environment.
Collapse
Affiliation(s)
- Abbie Jayne Parton
- School of Biomedical, Nutritional and Sport Sciences, Newcastle University, Newcastle Upon Tyne, United Kingdom
| | - Mark Waldron
- College of Engineering, Swansea University, Swansea, United Kingdom; School of Science and Technology, University of New England, Armidale, NSW, Australia
| | - Tom Clifford
- School of Sport, Health and Exercise Sciences, Loughborough University, Loughborough, United Kingdom
| | - Owen Jeffries
- School of Biomedical, Nutritional and Sport Sciences, Newcastle University, Newcastle Upon Tyne, United Kingdom.
| |
Collapse
|
35
|
Iwata R, Kawamura T, Hosokawa Y, Chang L, Suzuki K, Muraoka I. Differences between sexes in thermoregulatory responses and exercise time during endurance exercise in a hot environment following pre-cooling with ice slurry ingestion. J Therm Biol 2020; 94:102746. [PMID: 33292987 DOI: 10.1016/j.jtherbio.2020.102746] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 09/23/2020] [Accepted: 09/29/2020] [Indexed: 12/14/2022]
Abstract
This study aimed to examine differences between sexes in thermoregulatory responses and exercise time after ice slurry ingestion in a hot environment. Twenty-four healthy adults (male n = 12, body weight (BW) = 65.8 ± 10.3; female n = 12, BW = 58.2 ± 10.0) ingested 7.5 g/kg of either ice slurry at -1 °C (ICE) or control water at 20 °C (CON) before cycling at 55%VO2 max in a hot environment (controlled at 38 °C, 40% relative humidity). Rectal (Tre) and skin (Tsk) temperature, heart rate, sweat rate, respiratory gases, ratings of thermal sensation (TS), thermal comfort (TC), and rating of perceived exertion (RPE) were measured. Ice slurry did not improve exercise time in both sexes despite Tre was significantly lower in ICE than CON in both sexes. Tre, Tsk, HR, sweat rate and TS did not differ between sexes. TC and RPE in ICE were significantly higher during exercise in males than in females. In conclusion, there were no sex differences in the effects of pre-cooling with ice slurry ingestion; however, pre-cooling with ice slurry may be more effective in mitigating ratings of TC and RPE in females than males.
Collapse
Affiliation(s)
- Risa Iwata
- Waseda University, Graduate School of Sport Sciences, Saitama, Japan.
| | - Takuji Kawamura
- Waseda University, Faculty of Sport Sciences, Saitama, Japan
| | - Yuri Hosokawa
- Waseda University, Faculty of Sport Sciences, Saitama, Japan
| | - Lili Chang
- Waseda University, Graduate School of Sport Sciences, Saitama, Japan
| | | | - Isao Muraoka
- Waseda University, Faculty of Sport Sciences, Saitama, Japan
| |
Collapse
|
36
|
Barwood MJ, Gibson OR, Gillis DJ, Jeffries O, Morris NB, Pearce J, Ross ML, Stevens C, Rinaldi K, Kounalakis SN, Riera F, Mündel T, Waldron M, Best R. Menthol as an Ergogenic Aid for the Tokyo 2021 Olympic Games: An Expert-Led Consensus Statement Using the Modified Delphi Method. Sports Med 2020; 50:1709-1727. [PMID: 32623642 PMCID: PMC7497433 DOI: 10.1007/s40279-020-01313-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
INTRODUCTION Menthol topical application and mouth rinsing are ergogenic in hot environments, improving performance and perception, with differing effects on body temperature regulation. Consequently, athletes and federations are beginning to explore the possible benefits to elite sport performance for the Tokyo 2021 Olympics, which will take place in hot (~ 31 °C), humid (70% RH) conditions. There is no clear consensus on safe and effective menthol use for athletes, practitioners, or researchers. The present study addressed this shortfall by producing expert-led consensus recommendations. METHOD Fourteen contributors were recruited following ethical approval. A three-step modified Delphi method was used for voting on 96 statements generated following literature consultation; 192 statements total (96/96 topical application/mouth rinsing). Round 1 contributors voted to "agree" or "disagree" with statements; 80% agreement was required to accept statements. In round 2, contributors voted to "support" or "change" their round 1 unaccepted statements, with knowledge of the extant voting from round 1. Round 3 contributors met to discuss voting against key remaining statements. RESULTS Forty-seven statements reached consensus in round 1 (30/17 topical application/rinsing); 14 proved redundant. Six statements reached consensus in round 2 (2/4 topical application/rinsing); 116 statements proved redundant. Nine further statements were agreed in round 3 (6/3 topical application/rinsing) with caveats. DISCUSSION Consensus was reached on 62 statements in total (38/24 topical application/rinsing), enabling the development of guidance on safe menthol administration, with a view to enhancing performance and perception in the heat without impairing body temperature regulation.
Collapse
Affiliation(s)
- M J Barwood
- Department of Sport, Health and Nutrition, Leeds Trinity University, Brownberrie Lane, Horsforth, Leeds, LS18 5HD, UK.
| | - O R Gibson
- Centre for Human Performance, Exercise and Rehabilitation (CHPER), Department Life Sciences, Division of Sport, Health and Exercise Sciences, Brunel University London, Kingston Lane, Uxbridge, UB8 3PH, UK
| | - D J Gillis
- Human Performance Laboratory, Department of Sport and Movement Science, Salem State University, Salem, MA, 01970, USA
| | - O Jeffries
- School of Biomedical, Nutritional and Sport Sciences, Faculty of Medical Sciences, Newcastle University, Catherine Cookson Building, Newcastle Upon Tyne, NE2 4HH, UK
| | - N B Morris
- Department of Nutrition, Exercise and Sports, University of Copenhagen, 2100, Copenhagen, Denmark
| | - J Pearce
- Performance Nutrition Technical Lead, High Performance Sport New Zealand, Auckland, New Zealand
| | - M L Ross
- Australian Institute of Sport, Bruce, 2617, Australia
- Mary Mackillop Institute for Health Research, Australian Catholic University, Melbourne, 3000, Australia
| | - C Stevens
- School of Health and Human Sciences, Southern Cross University, Hogbin Dr, Coffs Harbour, NSW, 2450, Australia
| | - K Rinaldi
- Laboratoire ACTES (EA3596), Université des Antilles et de la Guyane, BP 250, 97157, Pointe-à-Pitre, France
- Arkea Samsic Pro Cycling Team, 35170, Bruz, France
| | - S N Kounalakis
- Faculty of Physical and Cultural Education, Evelpidon Hellenic Army Academy, Vari, Greece
| | - F Riera
- UPRES EA 35-96, UFR-STAPS, Université des Antilles et de la Guyane, BP 250, 97157, Pointe à Pitre Cedex, France
- Laboratoire Performance Santé Altitude, Université de Perpignan Via Domitia, UFR Sciences et Techniques des Activités Physiques et Sportives, 7 avenue Pierre de Coubertin, 66120, Font-Romeu, France
| | - T Mündel
- School of Sport Exercise and Nutrition, Massey University, Palmerston, New Zealand
| | - M Waldron
- College of Engineering, Applied Sports Science Technology and Medicine Research Centre (A-STEM), Swansea University Bay Campus, Swansea, Wales, UK
- School of Science and Technology, University of New England, Armidale, NSW, Australia
| | - R Best
- Centre for Sport Science and Human Performance, Waikato Institute of Technology, Hamilton, 3200, New Zealand
- School of Health and Social Care, Teesside University, Middlesbrough, Tees Valley, TS1 3BX, UK
| |
Collapse
|
37
|
Keringer P, Farkas N, Gede N, Hegyi P, Rumbus Z, Lohinai Z, Solymar M, Ruksakiet K, Varga G, Garami A. Menthol can be safely applied to improve thermal perception during physical exercise: a meta-analysis of randomized controlled trials. Sci Rep 2020; 10:13636. [PMID: 32788718 PMCID: PMC7423903 DOI: 10.1038/s41598-020-70499-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 07/27/2020] [Indexed: 02/03/2023] Open
Abstract
Menthol is often used as a cold-mimicking substance to allegedly enhance performance during physical activity, however menthol-induced activation of cold-defence responses during exercise can intensify heat accumulation in the body. This meta-analysis aimed at studying the effects of menthol on thermal perception and thermophysiological homeostasis during exercise. PubMed, EMBASE, Cochrane Library, and Google Scholar databases were searched until May 2020. Menthol caused cooler thermal sensation by weighted mean difference (WMD) of - 1.65 (95% CI, - 2.96 to - 0.33) and tended to improve thermal comfort (WMD = 1.42; 95% CI, - 0.13 to 2.96) during physical exercise. However, there was no meaningful difference in sweat production (WMD = - 24.10 ml; 95% CI, - 139.59 to 91.39 ml), deep body temperature (WMD = 0.02 °C; 95% CI, - 0.11 to 0.15 °C), and heart rate (WMD = 2.67 bpm; 95% CI - 0.74 to 6.09 bpm) between the treatment groups. Menthol improved the performance time in certain subgroups, which are discussed. Our findings suggest that different factors, viz., external application, warmer environment, and higher body mass index can improve menthol's effects on endurance performance, however menthol does not compromise warmth-defence responses during exercise, thus it can be safely applied by athletes from the thermoregulation point of view.
Collapse
Affiliation(s)
- Patrik Keringer
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pecs, 7624, Pecs, Hungary
| | - Nelli Farkas
- Institute for Translational Medicine, Szentagothai Research Centre, Medical School, University of Pecs, 7624, Pecs, Hungary
- Institute of Bioanalysis, Medical School, University of Pecs, 7624, Pecs, Hungary
| | - Noemi Gede
- Institute for Translational Medicine, Szentagothai Research Centre, Medical School, University of Pecs, 7624, Pecs, Hungary
| | - Peter Hegyi
- Institute for Translational Medicine, Szentagothai Research Centre, Medical School, University of Pecs, 7624, Pecs, Hungary
- Department of Translational Medicine, First Department of Medicine, Medical School, University of Pecs, 7624, Pecs, Hungary
| | - Zoltan Rumbus
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pecs, 7624, Pecs, Hungary
| | - Zsolt Lohinai
- Department of Conservative Dentistry, Faculty of Dentistry, Semmelweis University, 1088, Budapest, Hungary
| | - Margit Solymar
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pecs, 7624, Pecs, Hungary
| | - Kasidid Ruksakiet
- Department of Conservative Dentistry, Faculty of Dentistry, Semmelweis University, 1088, Budapest, Hungary
- Department of Oral Biology, Faculty of Dentistry, Semmelweis University, 1089, Budapest, Hungary
| | - Gabor Varga
- Department of Oral Biology, Faculty of Dentistry, Semmelweis University, 1089, Budapest, Hungary
| | - Andras Garami
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pecs, 7624, Pecs, Hungary.
| |
Collapse
|
38
|
Best R, Temm D, Hucker H, McDonald K. Repeated Menthol Mouth Swilling Affects Neither Strength nor Power Performance. Sports (Basel) 2020; 8:E90. [PMID: 32560472 PMCID: PMC7353636 DOI: 10.3390/sports8060090] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 06/05/2020] [Accepted: 06/16/2020] [Indexed: 01/05/2023] Open
Abstract
This study aimed to assess the effects of repeated menthol mouth swilling upon strength and power performance. Nineteen (10 male) participants completed familiarisation and experimental trials of repeated menthol mouth swilling (0.1% concentration) or control (no swill) in a randomised crossover design. Participants performed an isometric mid-thigh pull (IMTP; peak and mean force; N), vertical jump (peak; cm) and six second sprint (peak and mean power; W) under each condition. Participants completed three efforts per exercise task interspersed with three-minute recoveries. Mean best values were analysed via a two-way mixed repeated measures ANOVA, and differences reported as effect sizes ± 95% confidence intervals, with accompanying descriptors and p values. Differences in peak IMTP values were unclear between familiarisation and experimental trials, and between menthol and control conditions. Mean IMTP force differed between familiarisation and control (0.51; -0.15 to 1.14; p = 0.001) and familiarisation and menthol conditions (0.50; -0.15 to 1.14; p = 0.002) by a small degree, but were unclear between control and menthol conditions. Unclear differences were also noted on vertical jump performance compared to familiarisation and between experimental conditions, with repeated six second peak and average power performance also showing unclear effects across all comparisons. We conclude that repeated menthol mouth swilling does not improve strength or power performance.
Collapse
Affiliation(s)
- Russ Best
- Centre for Sport Science and Human Performance, Wintec, Hamilton 3200, New Zealand; (D.T.); (H.H.); (K.M.)
- School of Health and Life Sciences, Teesside University, Middlesbrough TS1 3BX, UK
| | - Dani Temm
- Centre for Sport Science and Human Performance, Wintec, Hamilton 3200, New Zealand; (D.T.); (H.H.); (K.M.)
| | - Holly Hucker
- Centre for Sport Science and Human Performance, Wintec, Hamilton 3200, New Zealand; (D.T.); (H.H.); (K.M.)
| | - Kerin McDonald
- Centre for Sport Science and Human Performance, Wintec, Hamilton 3200, New Zealand; (D.T.); (H.H.); (K.M.)
| |
Collapse
|
39
|
Khong TK, Selvanayagam V, Yusof A. Effect of glucose and sodium chloride mouth rinses on neuromuscular fatigue: a preliminary study. Eur J Sport Sci 2020; 21:224-230. [PMID: 32056510 DOI: 10.1080/17461391.2020.1730980] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Carbohydrate (CHO) mouth rinse has been shown to improve endurance performance and maintain the central drive of contracting muscles. Salt (NaCl) mouth rinse solution, often used in dentistry to desensitise the oral cavity to pain, could also activate cortical areas of the brain. Hence, the objective of this preliminary study was to investigate whether CHO (glucose) and NaCl mouth rinses could attenuate the reduction in maximum voluntary contraction (MVC) and sustained MVC (sMVC) following an endurance exercise (30-minute cycling at 70% VO2max). Ten subjects (male, age: 22 ± 1 years, weight: 65.3 ± 12.4 kg, height: 164.5 ± 7.5 cm, VO2max: 48.3 ± 6.1 mL kg-1 min-1) completed three trials of 30-minute cycling exercise. In a randomised cross-over study, in each trial, the participants rinsed using either water, 6% glucose, or 6% NaCl solution for 5 s immediately prior to and every 10 min during the cycling exercise. The MVC and sMVC were measured pre and post cycling. Analysis of variance showed significant interaction and time effects for MVC, while for sMVC there was a significant interaction with time and group effects. Both MVC and sMVC were higher post cycling in the glucose and NaCl groups compared to the water group, which suggests that activation of glucose and NaCl oral receptors could better preserve post-exercise force production. This is the first study to show that NaCl mouth rinse can produce a comparable effect on glucose. Hence, mouth rinses may be able to activate other distinct pathways that could attenuate fatigue.
Collapse
Affiliation(s)
- Teng Keen Khong
- Centre of Sport and Exercise Sciences, University of Malaya, Kuala Lumpur, Malaysia.,Faculty of Applied Sciences, Department of Sports Sciences, Tunku Abdul Rahman University College, Kuala Lumpur, Malaysia
| | - Victor Selvanayagam
- Centre of Sport and Exercise Sciences, University of Malaya, Kuala Lumpur, Malaysia
| | - Ashril Yusof
- Centre of Sport and Exercise Sciences, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
40
|
Douzi W, Dupuy O, Theurot D, Smolander J, Dugué B. Per-Cooling (Using Cooling Systems during Physical Exercise) Enhances Physical and Cognitive Performances in Hot Environments. A Narrative Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:E1031. [PMID: 32041228 PMCID: PMC7036802 DOI: 10.3390/ijerph17031031] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 01/25/2020] [Accepted: 01/29/2020] [Indexed: 12/19/2022]
Abstract
There are many important sport events that are organized in environments with a very hot ambient temperature (Summer Olympics, FIFA World Cup, Tour de France, etc.) and in hot locations (e.g., Qatar). Additionally, in the context of global warming and heat wave periods, athletes are often subjected to hot ambient temperatures. It is known that exercising in the heat induces disturbances that may provoke premature fatigue and negatively affects overall performance in both endurance and high intensity exercises. Deterioration in several cognitive functions may also occur, and individuals may be at risk for heat illnesses. To train, perform, work and recover and in a safe and effective way, cooling strategies have been proposed and have been routinely applied before, during and after exercise. However, there is a limited understanding of the influences of per-cooling on performance, and it is the subject of the present review. This work examines the influences of per-cooling of different areas of the body on performance in terms of intense short-term exercises ("anaerobic" exercises), endurance exercises ("aerobic" exercises), and cognitive functioning and provides detailed strategies that can be applied when individuals train and/or perform in high ambient temperatures.
Collapse
Affiliation(s)
| | | | | | | | - Benoit Dugué
- University of Poitiers, Laboratoire Mobilité Vieillissement Exercice (MOVE)-EA6314, Faculty of Sport Sciences, 8 Allée Jean Monnet, 86000 Poitiers, France; (W.D.); (O.D.); (D.T.); (J.S.)
| |
Collapse
|
41
|
Saldaris JM, Landers GJ, Lay BS. Physical and perceptual cooling: Improving cognitive function, mood disturbance and time to fatigue in the heat. Scand J Med Sci Sports 2020; 30:801-811. [DOI: 10.1111/sms.13623] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 11/18/2019] [Accepted: 12/22/2019] [Indexed: 12/19/2022]
Affiliation(s)
- Jacinta M. Saldaris
- School of Human Sciences (Exercise and Sport Science) The University of Western Australia Western Australia Perth Australia
| | - Grant J. Landers
- School of Human Sciences (Exercise and Sport Science) The University of Western Australia Western Australia Perth Australia
| | - Brendan S. Lay
- School of Human Sciences (Exercise and Sport Science) The University of Western Australia Western Australia Perth Australia
| |
Collapse
|
42
|
Taylor L, Stevens CJ, Thornton HR, Poulos N, Chrismas BCR. Limiting the Rise in Core Temperature During a Rugby Sevens Warm-Up With an Ice Vest. Int J Sports Physiol Perform 2019; 14:1212-1218. [PMID: 30840530 DOI: 10.1123/ijspp.2018-0821] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 01/17/2019] [Accepted: 02/05/2019] [Indexed: 10/27/2023]
Abstract
PURPOSE To determine how a cooling vest worn during a warm-up could influence selected performance (countermovement jump [CMJ]), physical (global positioning system [GPS] metrics), and psychophysiological (body temperature and perceptual) variables. METHODS In a randomized, crossover design, 12 elite male World Rugby Sevens Series athletes completed an outdoor (wet bulb globe temperature 23-27°C) match-specific externally valid 30-min warm-up wearing a phase-change cooling vest (VEST) and without (CONTROL), on separate occasions 7 d apart. CMJ was assessed before and after the warm-up, with GPS indices and heart rate monitored during the warm-ups, while core temperature (Tc; ingestible telemetric pill; n = 6) was recorded throughout the experimental period. Measures of thermal sensation (TS) and thermal comfort (TC) was obtained pre-warm-up and post-warm-up, with rating of perceived exertion (RPE) taken post-warm-ups. RESULTS Athletes in VEST had a lower ΔTc (mean [SD]: VEST = 1.3°C [0.1°C]; CONTROL = 2.0°C [0.2°C]) from pre-warm-up to post-warm-up (effect size; ±90% confidence limit: -1.54; ±0.62) and Tc peak (mean [SD]: VEST = 37.8°C [0.3°C]; CONTROL = 38.5°C [0.3°C]) at the end of the warm-up (-1.59; ±0.64) compared with CONTROL. Athletes in VEST demonstrated a decrease in ΔTS (-1.59; ±0.72) and ΔTC (-1.63; ±0.73) pre-warm-up to post-warm-up, with a lower RPE post-warm-up (-1.01; ±0.46) than CONTROL. Changes in CMJ and GPS indices were trivial between conditions (effect size < 0.2). CONCLUSIONS Wearing the vest prior to and during a warm-up can elicit favorable alterations in physiological (Tc) and perceptual (TS, TC, and RPE) warm-up responses, without compromising the utilized warm-up characteristics or physical-performance measures.
Collapse
|
43
|
The Impact of an Ice Slurry-Induced Gastrointestinal Heat Sink on Gastrointestinal and Rectal Temperatures Following Exercise. Sports (Basel) 2019; 7:sports7090198. [PMID: 31461848 PMCID: PMC6784097 DOI: 10.3390/sports7090198] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 08/11/2019] [Accepted: 08/22/2019] [Indexed: 01/08/2023] Open
Abstract
Gastrointestinal temperature (Tgint) measurement with a telemetric pill (TP) is increasingly used in exercise science. Contact of cool water with a TP invalidates Tgint assessment. However, what effect a heat sink created in the proximity of a TP may have on the assessment of Tgint remains unknown. We examined the impact of an ice slurry-induced heat sink on Tgint and rectal temperature (Trec) following exercise. After 20 min of seating (20–22 °C, 25–40% relative humidity (RH)), 11 men completed two intersperse exercise periods (31–32 °C, 35% RH) at 75–80% of estimated maximal heart rate until a Trec increase of 1 °C above baseline level. Following the first exercise period, participants were seated for 45 min and ingested 7.5 g·kg−1 of thermoneutral water, whereas, following the second period, they ingested 7.5 g·kg−1 of ice slurry. Both Tgint and Trec were measured continuously. The TPs were swallowed 10 h prior to the experiments. A bias ≤0.27 °C was taken as an indication that Tgint and Trec provided similar core temperature indices. Mean biases and 95% limits of agreement during passive sitting, first exercise, water ingestion, second exercise, and ice slurry ingestion periods were 0.16 ± 0.53, 0.13 ± 0.41, 0.21 ± 0.70, 0.17 ± 0.50, and 0.18 ± 0.66 °C, respectively. The rates of decrease in Tgint and Trec did not differ between the water and ice slurry ingestion periods. Our results indicate that ice slurry ingestion following exercise does not impact TP-derived assessment of Tgint compared with Trec.
Collapse
|
44
|
Hermand E, Chabert C, Hue O. Ultra-endurance events in tropical environments and countermeasures to optimize performances and health. Int J Hyperthermia 2019; 36:753-760. [PMID: 31429600 DOI: 10.1080/02656736.2019.1635718] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Physical performance in a tropical environment, combining high heat and humidity, is a difficult physiological challenge that requires specific preparation. The elevated humidity of a tropical climate impairs the thermoregulatory mechanisms by limiting the rate of sweat evaporation. Hence, a proper management of whole-body temperature is required to complete an ultra-endurance event in such an environment. In these long-duration events, which can last from 8 to 20 h, held in hot and humid settings, performance is tightly linked to the ability in maintaining an optimal hydration status. Indeed, the rate of withdrawal in these longer races was associated with lower water intake, and the majority of finishers exhibited alterations in electrolyte balance (e.g., sodium). Hence, this work reviews the effects on performance of high heat and humidity in two representative ultra-endurance sports, ultramarathons and long-distance triathlons, and several countermeasures to counteract the impact of these harsh environmental stresses and maintain a high level of performance, such as hydration, cooling strategies and heat acclimation.
Collapse
Affiliation(s)
- E Hermand
- Laboratory « Adaptations au Climat Tropical, Exercice et Santé » (EA 3596 ACTES), French West Indies University , Pointe-à-Pitre , France.,Laboratory « Handicap, Activité, Vieillissement, Autonomie, Environnement » (EA 6310 HAVAE), University of Limoges , Limoges , France
| | - C Chabert
- Laboratory « Adaptations au Climat Tropical, Exercice et Santé » (EA 3596 ACTES), French West Indies University , Pointe-à-Pitre , France
| | - O Hue
- Laboratory « Adaptations au Climat Tropical, Exercice et Santé » (EA 3596 ACTES), French West Indies University , Pointe-à-Pitre , France
| |
Collapse
|
45
|
Douzi W, Dugué B, Vinches L, Al Sayed C, Hallé S, Bosquet L, Dupuy O. Cooling during exercise enhances performances, but the cooled body areas matter: A systematic review with meta‐analyses. Scand J Med Sci Sports 2019; 29:1660-1676. [DOI: 10.1111/sms.13521] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2018] [Revised: 07/10/2019] [Accepted: 07/17/2019] [Indexed: 11/30/2022]
Affiliation(s)
- Wafa Douzi
- Laboratoire Mobilité Vieillissement Exercice (MOVE)‐EA6314, Faculty of Sport Sciences University of Poitiers Poitiers France
| | - Benoit Dugué
- Laboratoire Mobilité Vieillissement Exercice (MOVE)‐EA6314, Faculty of Sport Sciences University of Poitiers Poitiers France
| | - Ludwig Vinches
- Department of Mechanical Engineering ‐ Ecole de Technologie Supérieure Montréal QC Canada
| | - Chady Al Sayed
- Department of Mechanical Engineering ‐ Ecole de Technologie Supérieure Montréal QC Canada
| | - Stéphane Hallé
- Department of Mechanical Engineering ‐ Ecole de Technologie Supérieure Montréal QC Canada
| | - Laurent Bosquet
- Laboratoire Mobilité Vieillissement Exercice (MOVE)‐EA6314, Faculty of Sport Sciences University of Poitiers Poitiers France
| | - Olivier Dupuy
- Laboratoire Mobilité Vieillissement Exercice (MOVE)‐EA6314, Faculty of Sport Sciences University of Poitiers Poitiers France
| |
Collapse
|
46
|
Griggs KE, Stephenson BT, Price MJ, Goosey-Tolfrey VL. Heat-related issues and practical applications for Paralympic athletes at Tokyo 2020. Temperature (Austin) 2019; 7:37-57. [PMID: 32166104 PMCID: PMC7053936 DOI: 10.1080/23328940.2019.1617030] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 05/02/2019] [Accepted: 05/06/2019] [Indexed: 02/07/2023] Open
Abstract
International sporting competitions, including the Paralympic Games, are increasingly being held in hot and/or humid environmental conditions. Thus, a greater emphasis is being placed on preparing athletes for the potentially challenging environmental conditions of the host cities, such as the upcoming Games in Tokyo in 2020. However, evidence-based practices are limited for the impairment groups that are eligible to compete in Paralympic sport. This review aims to provide an overview of heat-related issues for Paralympic athletes alongside current recommendations to reduce thermal strain and technological advancements in the lead up to the Tokyo 2020 Paralympic Games. When competing in challenging environmental conditions, a number of factors may contribute to an athlete's predisposition to heightened thermal strain. These include the characteristics of the sport itself (type, intensity, duration, modality, and environmental conditions), the complexity and severity of the impairment and classification of the athlete. For heat vulnerable Paralympic athletes, strategies such as the implementation of cooling methods and heat acclimation can be used to combat the increase in heat strain. At an organizational level, regulations and specific heat policies should be considered for several Paralympic sports. Both the utilization of individual strategies and specific heat health policies should be employed to ensure that Paralympics athletes' health and sporting performance are not negatively affected during the competition in the heat at the Tokyo 2020 Paralympic Games.
Collapse
Affiliation(s)
- Katy E. Griggs
- Department of Engineering, School of Science and Technology, Nottingham Trent University, Nottingham, UK
| | - Ben T. Stephenson
- Loughborough Performance Centre, English Institute of Sport, Loughborough University, Loughborough, UK
- Peter Harrison Centre for Disability Sport, School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Michael J. Price
- School of Life Sciences, Centre for Sport, Exercise and Life Sciences, Coventry University, Coventry, UK
| | - Victoria L. Goosey-Tolfrey
- Peter Harrison Centre for Disability Sport, School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| |
Collapse
|
47
|
Coudevylle GR, Sinnapah S, Robin N, Collado A, Hue O. Conventional and Alternative Strategies to Cope With the Subtropical Climate of Tokyo 2020: Impacts on Psychological Factors of Performance. Front Psychol 2019; 10:1279. [PMID: 31214085 PMCID: PMC6558207 DOI: 10.3389/fpsyg.2019.01279] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Accepted: 05/15/2019] [Indexed: 12/01/2022] Open
Abstract
The thermal discomfort caused by a hot or hot-wet climate can have negative effects on human performance. The 2020 Summer Olympic and Paralympic Games will take place in Tokyo’s hot and humid summer period, possibly exposing athletes to severe environmental stressors. In addition to technical, tactical, physical and nutritional preparation, Olympians and Paralympians need an optimal psychological state to turn in their best performances, especially in terms of emotional control, concentration and motivation. Yet, the tropical climate can have many negative effects on these factors. Better understanding of the negative effects of this climate and the strategies to manage them might be crucial for competitors, coaches and their teams in Japan. At the psychological level, cooling interventions before, during and/or immediately after exercise were mainly studied on perceptual responses. However, the effects of these interventions on other psychological components such as cognitive abilities or psychological states and the use of psychological techniques have been little explored, especially in hot-wet climate. Thus, this article proposes to take stock of the knowledge on the conventional and alternative strategies that help athletes to psychologically cope with the subtropical climate of Tokyo.
Collapse
Affiliation(s)
- Guillaume R Coudevylle
- Laboratory ACTES (UPRES-EA 3596), University of the French West Indies, Pointe-à-Pitre, France
| | - Stéphane Sinnapah
- Laboratory ACTES (UPRES-EA 3596), University of the French West Indies, Pointe-à-Pitre, France
| | - Nicolas Robin
- Laboratory ACTES (UPRES-EA 3596), University of the French West Indies, Pointe-à-Pitre, France
| | - Aurélie Collado
- Laboratory ACTES (UPRES-EA 3596), University of the French West Indies, Pointe-à-Pitre, France
| | - Olivier Hue
- Laboratory ACTES (UPRES-EA 3596), University of the French West Indies, Pointe-à-Pitre, France
| |
Collapse
|
48
|
Jeffries O, Waldron M. The effects of menthol on exercise performance and thermal sensation: A meta-analysis. J Sci Med Sport 2019; 22:707-715. [DOI: 10.1016/j.jsams.2018.12.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 11/02/2018] [Accepted: 12/02/2018] [Indexed: 12/13/2022]
|
49
|
Alhadad SB, Tan PMS, Lee JKW. Efficacy of Heat Mitigation Strategies on Core Temperature and Endurance Exercise: A Meta-Analysis. Front Physiol 2019; 10:71. [PMID: 30842739 PMCID: PMC6391927 DOI: 10.3389/fphys.2019.00071] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Accepted: 01/21/2019] [Indexed: 11/26/2022] Open
Abstract
Background: A majority of high profile international sporting events, including the coming 2020 Tokyo Olympics, are held in warm and humid conditions. When exercising in the heat, the rapid rise of body core temperature (Tc) often results in an impairment of exercise capacity and performance. As such, heat mitigation strategies such as aerobic fitness (AF), heat acclimation/acclimatization (HA), pre-exercise cooling (PC) and fluid ingestion (FI) can be introduced to counteract the debilitating effects of heat strain. We performed a meta-analysis to evaluate the effectiveness of these mitigation strategies using magnitude-based inferences. Methods: A computer-based literature search was performed up to 24 July 2018 using the electronic databases: PubMed, SPORTDiscus and Google Scholar. After applying a set of inclusion and exclusion criteria, a total of 118 studies were selected for evaluation. Each study was assessed according to the intervention's ability to lower Tc before exercise, attenuate the rise of Tc during exercise, extend Tc at the end of exercise and improve endurance. Weighted averages of Hedges' g were calculated for each strategy. Results: PC (g = 1.01) was most effective in lowering Tc before exercise, followed by HA (g = 0.72), AF (g = 0.65), and FI (g = 0.11). FI (g = 0.70) was most effective in attenuating the rate of rise of Tc, followed by HA (g = 0.35), AF (g = −0.03) and PC (g = −0.46). In extending Tc at the end of exercise, AF (g = 1.11) was most influential, followed by HA (g = −0.28), PC (g = −0.29) and FI (g = −0.50). In combination, AF (g = 0.45) was most effective at favorably altering Tc, followed by HA (g = 0.42), PC (g = 0.11) and FI (g = 0.09). AF (1.01) was also found to be most effective in improving endurance, followed by HA (0.19), FI (−0.16) and PC (−0.20). Conclusion: AF was found to be the most effective in terms of a strategy's ability to favorably alter Tc, followed by HA, PC and lastly, FI. Interestingly, a similar ranking was observed in improving endurance, with AF being the most effective, followed by HA, FI, and PC. Knowledge gained from this meta-analysis will be useful in allowing athletes, coaches and sport scientists to make informed decisions when employing heat mitigation strategies during competitions in hot environments.
Collapse
Affiliation(s)
- Sharifah Badriyah Alhadad
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore, Singapore.,Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
| | - Pearl M S Tan
- Defence Medical & Environmental Research Institute, DSO National Laboratories, Singapore, Singapore
| | - Jason K W Lee
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Defence Medical & Environmental Research Institute, DSO National Laboratories, Singapore, Singapore.,Department of Orthopaedic Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| |
Collapse
|
50
|
Abstract
CONTEXT Precooling and midevent cooling of the torso using cooling vests can improve exercise performance in the heat with or without physiological changes; however, the effects of such cooling during intermittent exercise in the heat are unknown. OBJECTIVE To investigate the effects of torso cooling during intermittent exercise in the heat (35°C, 50% relative humdity) on sprint performance and the physiological and perceptual responses to the exercise. DESIGN Crossover study. SETTING Walk-in environmental chamber. PATIENTS OR OTHER PARTICIPANTS Ten non-heat-acclimated, male soccer players (age = 25 ± 2 years, height = 1.77 ± 0.06 m, mass = 72.9 ± 7.6 kg). INTERVENTION(S) Two 90-minute bouts of soccer-specific intermittent running in the heat: 1 trial with a cooling vest worn during the exercise and 1 trial without a cooling vest. Each trial comprised two 45-minute periods separated by approximately 15 minutes of seated rest in cool conditions (approximately 23°C, 50% relative humdity). MAIN OUTCOME MEASURE(S) Peak sprint speed, rectal temperature (Tr), mean-weighted skin temperature (Tsk), heart rate (HR), rating of perceived exertion (RPE), and thermal sensation (TS) were measured every 5 minutes. RESULTS Peak sprint performance was largely unaffected by the cooling vest. The Tr, Tsk, HR, RPE, and TS were unaffected in the cooling-vest trial during the first 45 minutes, but Tr rose at a slower rate in the cooling-vest trial (0.026°C.min-1 ± 0.008°C.min-1) than in the no-vest trial (0.032°C.min-1 ± 0.009°C.min-1). During the second 45-minute period, Tr, Tr rate of rise, Tsk, RPE, and TS were lower in the cooling-vest trial (Hedges g range, 0.55-0.84), but mean HR was unaffected. CONCLUSIONS Wearing a cooling vest during soccer-specific intermittent running in the heat reduced physiological and perceptual strain but did not increase peak sprint speed.
Collapse
Affiliation(s)
- Kirstie Parris
- Department of Life Sciences, University of Roehampton, Whitelands College, London, United Kingdom
| | - Christopher J Tyler
- Department of Life Sciences, University of Roehampton, Whitelands College, London, United Kingdom
| |
Collapse
|