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Burtscher J, Raberin A, Brocherie F, Malatesta D, Manferdelli G, Citherlet T, Krumm B, Bourdillon N, Antero J, Rasica L, Burtscher M, Millet GP. Recommendations for Women in Mountain Sports and Hypoxia Training/Conditioning. Sports Med 2024; 54:795-811. [PMID: 38082199 PMCID: PMC11052836 DOI: 10.1007/s40279-023-01970-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/06/2023] [Indexed: 04/28/2024]
Abstract
The (patho-)physiological responses to hypoxia are highly heterogeneous between individuals. In this review, we focused on the roles of sex differences, which emerge as important factors in the regulation of the body's reaction to hypoxia. Several aspects should be considered for future research on hypoxia-related sex differences, particularly altitude training and clinical applications of hypoxia, as these will affect the selection of the optimal dose regarding safety and efficiency. There are several implications, but there are no practical recommendations if/how women should behave differently from men to optimise the benefits or minimise the risks of these hypoxia-related practices. Here, we evaluate the scarce scientific evidence of distinct (patho)physiological responses and adaptations to high altitude/hypoxia, biomechanical/anatomical differences in uphill/downhill locomotion, which is highly relevant for exercising in mountainous environments, and potentially differential effects of altitude training in women. Based on these factors, we derive sex-specific recommendations for mountain sports and intermittent hypoxia conditioning: (1) Although higher vulnerabilities of women to acute mountain sickness have not been unambiguously shown, sex-dependent physiological reactions to hypoxia may contribute to an increased acute mountain sickness vulnerability in some women. Adequate acclimatisation, slow ascent speed and/or preventive medication (e.g. acetazolamide) are solutions. (2) Targeted training of the respiratory musculature could be a valuable preparation for altitude training in women. (3) Sex hormones influence hypoxia responses and hormonal-cycle and/or menstrual-cycle phases therefore may be factors in acclimatisation to altitude and efficiency of altitude training. As many of the recommendations or observations of the present work remain partly speculative, we join previous calls for further quality research on female athletes in sports to be extended to the field of altitude and hypoxia.
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Affiliation(s)
- Johannes Burtscher
- Institute of Sport Sciences, Faculty of Biology and Medicine, University of Lausanne, Building Synathlon, Campus Dorigny, 1015, Lausanne, Switzerland
| | - Antoine Raberin
- Institute of Sport Sciences, Faculty of Biology and Medicine, University of Lausanne, Building Synathlon, Campus Dorigny, 1015, Lausanne, Switzerland
| | - Franck Brocherie
- Laboratory Sport, Expertise and Performance (EA 7370), French Institute of Sport, Paris, France
| | - Davide Malatesta
- Institute of Sport Sciences, Faculty of Biology and Medicine, University of Lausanne, Building Synathlon, Campus Dorigny, 1015, Lausanne, Switzerland
| | - Giorgio Manferdelli
- Institute of Sport Sciences, Faculty of Biology and Medicine, University of Lausanne, Building Synathlon, Campus Dorigny, 1015, Lausanne, Switzerland
| | - Tom Citherlet
- Institute of Sport Sciences, Faculty of Biology and Medicine, University of Lausanne, Building Synathlon, Campus Dorigny, 1015, Lausanne, Switzerland
| | - Bastien Krumm
- Institute of Sport Sciences, Faculty of Biology and Medicine, University of Lausanne, Building Synathlon, Campus Dorigny, 1015, Lausanne, Switzerland
| | - Nicolas Bourdillon
- Institute of Sport Sciences, Faculty of Biology and Medicine, University of Lausanne, Building Synathlon, Campus Dorigny, 1015, Lausanne, Switzerland
| | - Juliana Antero
- Institut de Recherche Bio-Médicale Et d'Épidémiologie du Sport (EA 7329), French Institute of Sport, Paris, France
| | - Letizia Rasica
- Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
| | - Martin Burtscher
- Department of Sport Science, University of Innsbruck, Innsbruck, Austria
| | - Grégoire P Millet
- Institute of Sport Sciences, Faculty of Biology and Medicine, University of Lausanne, Building Synathlon, Campus Dorigny, 1015, Lausanne, Switzerland.
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2
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Pellicer-Caller R, Vaquero-Cristóbal R, González-Gálvez N, Abenza-Cano L, Horcajo J, de la Vega-Marcos R. Influence of Exogenous Factors Related to Nutritional and Hydration Strategies and Environmental Conditions on Fatigue in Endurance Sports: A Systematic Review with Meta-Analysis. Nutrients 2023; 15:2700. [PMID: 37375605 DOI: 10.3390/nu15122700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 05/31/2023] [Accepted: 06/06/2023] [Indexed: 06/29/2023] Open
Abstract
The aim of this systematic review with meta-analysis was to examine the influence of exogenous factors related to nutritional and hydration strategies and environmental conditions, as modulators of fatigue, including factors associated with performance fatigability and perceived fatigability, in endurance tests lasting 45 min to 3 h. A search was carried out using four databases: PubMed, Web of Science, SPORTDiscus, and EBSCO. A total of 5103 articles were screened, with 34 included in the meta-analysis. The review was registered with PROSPERO (CRD42022327203) and adhered to the PRISMA guidelines. The study quality was evaluated according to the PEDro score and assessed using Rosenthal's fail-safe N. Carbohydrate (CHO) intake increased the time to exhaustion (p < 0.001) and decreased the heart rate (HR) during the test (p = 0.018). Carbohydrate with protein intake (CHO + PROT) increased lactate during the test (p = 0.039). With respect to hydration, dehydrated individuals showed a higher rate of perceived exertion (RPE) (p = 0.016) and had a higher body mass loss (p = 0.018). In hot conditions, athletes showed significant increases in RPE (p < 0.001), HR (p < 0.001), and skin temperature (p = 0.002), and a decrease in the temperature gradient (p < 0.001) after the test. No differences were found when athletes were subjected to altitude or cold conditions. In conclusion, the results revealed that exogenous factors, such as nutritional and hydration strategies, as well as environmental conditions, affected fatigue in endurance sports, including factors associated with performance fatigability and perceived fatigability.
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Affiliation(s)
- Roberto Pellicer-Caller
- Facultad de Deporte, UCAM Universidad Católica de Murcia, 30107 Murcia, Spain
- Caller Energy Labs, Caller SportEnergy S.L., 39005 Santander, Spain
| | | | | | - Lucía Abenza-Cano
- Facultad de Deporte, UCAM Universidad Católica de Murcia, 30107 Murcia, Spain
| | - Javier Horcajo
- Department of Social Psychology and Methodology, Autonomous University of Madrid, 28049 Madrid, Spain
| | - Ricardo de la Vega-Marcos
- Department of Physical Education, Sport and Human Movement, Autonomous University of Madrid, 28049 Madrid, Spain
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3
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Atalağ O, Gotshalk L. Travel related changes in performance and physiological markers: the effects of eastward travel on female basketball players. J Phys Ther Sci 2023; 35:399-407. [PMID: 37266356 PMCID: PMC10231977 DOI: 10.1589/jpts.35.399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 02/23/2023] [Indexed: 06/03/2023] Open
Abstract
[Purpose] Purpose of this study is to measure the changes in various physiological markers and performance criteria for women basketball players over the course of a travel heavy season. [Participants and Methods] Fifty one Division-II female basketball players and a control group of 54 females joined this study. Measurements began at the beginning of the competitive season and concluded with final measurements at the end of the competitive season. [Results] The female basketball players showed noticeable increases in resting salivary cortisol, visceral trunk fat, resting heart rate, and resting blood pressure. These athletes also showed diminishment in isokinetic force of leg muscles, particularly in knee flexion strength. Vertical jump measurements also indicated a slight diminishment. In contrast, the control group experienced none of the same changes. [Conclusion] Over the course of a grueling flight schedule in combination with a full-length basketball season, the female athletes in this study showed significant declinations in many indicators of overall health. It is concluded that resulting prolonged intermittent stress of a travel-heavy season can lead to significant changes in certain physiological markers with notable decreases in isokinetic force of leg muscle.
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Affiliation(s)
- Ozan Atalağ
- Department of Kinesiology and Exercise Sciences, University
of Hawaii at Hilo: 200W Kawili Street, Hilo, Hawaii 96720, USA
| | - Lincoln Gotshalk
- Department of Kinesiology and Exercise Sciences, University
of Hawaii at Hilo: 200W Kawili Street, Hilo, Hawaii 96720, USA
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Guerrero-Pinzón JJ, Alcantara JM, García-Buendia G, Mochón-Benguigui S, Ramírez-Maldonado M, Ruiz JR, Jurado-Fasoli L. A nutritional intervention for moderate altitude endurance preparation: A case report. J Int Soc Sports Nutr 2022; 19:650-663. [DOI: 10.1080/15502783.2022.2140596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Affiliation(s)
- Juan J. Guerrero-Pinzón
- PROmoting FITness and Health through Physical Activity Research Group (PROFITH), Sport and Health University Research Institute (iMUDS), University of Granada, Department of Physical Education and Sports, Faculty of Sport Sciences, Granada, Spain
| | - Juan M.A. Alcantara
- PROmoting FITness and Health through Physical Activity Research Group (PROFITH), Sport and Health University Research Institute (iMUDS), University of Granada, Department of Physical Education and Sports, Faculty of Sport Sciences, Granada, Spain
| | - Gustavo García-Buendia
- University of Granada, Department Physical Education and Sports, Faculty of Sport Sciences, Granada, Spain
| | - Sol Mochón-Benguigui
- University of Granada, Department of Physiology. Faculty of Medicine, Granada, Spain
| | - Mauricio Ramírez-Maldonado
- PROmoting FITness and Health through Physical Activity Research Group (PROFITH), Sport and Health University Research Institute (iMUDS), University of Granada, Department of Physical Education and Sports, Faculty of Sport Sciences, Granada, Spain
| | - Jonatan R. Ruiz
- PROmoting FITness and Health through Physical Activity Research Group (PROFITH), Sport and Health University Research Institute (iMUDS), University of Granada, Department of Physical Education and Sports, Faculty of Sport Sciences, Granada, Spain
- Instituto de Investigación Biosanitaria, ibs.Granada, Granada, Spain
| | - Lucas Jurado-Fasoli
- PROmoting FITness and Health through Physical Activity Research Group (PROFITH), Sport and Health University Research Institute (iMUDS), University of Granada, Department of Physical Education and Sports, Faculty of Sport Sciences, Granada, Spain
- University of Granada, Department of Physiology. Faculty of Medicine, Granada, Spain
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Swinnen W, Laughlin E, Hoogkamer W. Everesting: cycling the elevation of the tallest mountain on Earth. Eur J Appl Physiol 2022; 122:2565-2574. [PMID: 36064982 PMCID: PMC9444120 DOI: 10.1007/s00421-022-05032-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 08/18/2022] [Indexed: 12/02/2022]
Abstract
Purpose With few cycling races on the calendar in 2020 due to COVID-19, Everesting became a popular challenge: you select one hill and cycle up and down it until you reach the accumulated elevation of Mt. Everest (8,848 m or 29,029ft). With an almost infinite number of different hills across the world, the question arises what the optimal hill for Everesting would be. Here, we address the biomechanics and energetics of up- and downhill cycling to determine the characteristics of this optimal hill. Methods During uphill cycling, the mechanical power output equals the power necessary to overcome air resistance, rolling resistance, and work against gravity, and for a fast Everesting time, one should maximize this latter term. To determine the optimal section length (i.e., number of repetitions), we applied the critical power concept and assumed that the U-turn associated with an additional repetition comes with a 6 s time penalty. Results To use most mechanical power to overcoming gravity, slopes of at least 12% are most suitable, especially since gross efficiency seems only minimally diminished on steeper slopes. Next, we found 24 repetitions to be optimal, yet this number slightly depends on the assumptions made. Finally, we discuss other factors (fueling, altitude, fatigue) not incorporated in the model but also affecting Everesting performances. Conclusion For a fast Everesting time, our model suggests to select a hill climb which preferably starts at (or close to) sea level, with a slope of 12–20% and length of 2–3 km.
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Affiliation(s)
- Wannes Swinnen
- Human Movement Biomechanics Research Group, Department of Movement Science, KU Leuven, Tervuursevest 101, Mailbox 1501, 3001, Louvain, Belgium.
| | - Emily Laughlin
- Integrative Locomotion Laboratory, Department of Kinesiology, University of Massachusetts, Amherst, USA
| | - Wouter Hoogkamer
- Integrative Locomotion Laboratory, Department of Kinesiology, University of Massachusetts, Amherst, USA
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Kontro H, Bertagnolli C, Murias JM, MacInnis MJ. Impairment in maximal lactate steady state after carbon monoxide inhalation is related to training status. Exp Physiol 2022; 107:1265-1282. [PMID: 36029041 DOI: 10.1113/ep090642] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 08/17/2022] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? What is the effect of an elevated COHb concentration following carbon monoxide inhalation on the maximal lactate steady state (MLSS) in humans and is this effect dependent on aerobic fitness? What is the main finding and its importance? An elevated COHb concentration intensified physiological responses to exercise at the MLSS- including heart rate, ventilation, and peripheral fatigue-in all participants and reduced the MLSS (i.e., destabilized the blood lactate concentration) in trained but not untrained males and females. ABSTRACT This study investigated whether a lower effective [Hb], induced by carbon monoxide (CO) inhalation, reduces the peak oxygen uptake (V̇O2 peak) and the maximal lactate steady state (MLSS) and whether training status explains individual variation in these impairments. Healthy young participants completed two ramp incremental tests (n = 20 [10 female]) and two trials at MLSS (n = 16 [8 female]) following CO rebreathe tests and sham procedures (SHAM) in random orders. All fitness variables were normalized to fat-free mass (FFM) to account for sex-related differences in body composition, and males and females were matched for aerobic fitness. The V̇O2 peak (mean [SD]: -4.2 [3.7]%), peak power output (-3.3 [2.2]%), and respiratory compensation point (-6.3 [4.5]%) were reduced in CO compared with SHAM (P < 0.001 for all), but the gas exchange threshold (-3.3 [7.1]%) was not (P = 0.077). Decreases in V̇O2 peak (r = -0.45; P = 0.047) and peak power output (r = -0.49; P = 0.029) in CO were correlated with baseline aerobic fitness. Compared to SHAM, physiological and perceptual indicators of exercise-related stress were exacerbated by CO while cycling at MLSS. Notably, the mean blood lactate concentration ([La]) increased (i.e., Δ[La] > 1.0 mM) between 10 min (5.5 [1.4] mM) and 30 min (6.8 [1.3] mM; P = 0.026) in CO, with 9/16 participants classified as unstable. These unstable participants had a higher V̇O2 peak (66.2 [8.5] vs. 56.4 [8.8] mL·kg FFM-1 ·min-1 , P = 0.042) and V̇O2 at MLSS (55.8 vs. 44.3 mL·kg FFM-1 ·min-1 , P = 0.006) compared to the stable group. In conclusion, a reduced O2 -carrying capacity decreased maximal and submaximal exercise performance, with higher aerobic fitness associated with greater impairments in both. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Hilkka Kontro
- Faculty of Kinesiology, Human Performance Lab, University of Calgary, Canada
| | - Craig Bertagnolli
- Faculty of Kinesiology, Human Performance Lab, University of Calgary, Canada
| | - Juan M Murias
- Faculty of Kinesiology, Human Performance Lab, University of Calgary, Canada
| | - Martin J MacInnis
- Faculty of Kinesiology, Human Performance Lab, University of Calgary, Canada
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7
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Draper S, Singer T, Dulaney C, McDaniel J. Single Leg Cycling Offsets Reduced Muscle Oxygenation in Hypoxic Environments. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19159139. [PMID: 35897502 PMCID: PMC9331301 DOI: 10.3390/ijerph19159139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 07/19/2022] [Accepted: 07/21/2022] [Indexed: 12/04/2022]
Abstract
The intensity of large muscle mass exercise declines at altitude due to reduced oxygen delivery to active muscles. The purpose of this investigation was to determine if the greater limb blood flow during single-leg cycling prevents the reduction in tissue oxygenation observed during traditional double-leg cycling in hypoxic conditions. Ten healthy individuals performed bouts of double and single-leg cycling (4, four-minute stages at 50−80% of their peak oxygen consumption) in hypoxic (15% inspired O2) and normoxic conditions. Heart rate, mean arterial pressure, femoral blood flow, lactate, oxygenated hemoglobin, total hemoglobin, and tissue saturation index in the vastus lateralis were recorded during cycling tests. Femoral blood flow (2846 ± 912 mL/min) and oxygenated hemoglobin (−2.98 ± 3.56 au) during single-leg cycling in hypoxia were greater than double-leg cycling in hypoxia (2429 ± 835 mL/min and −6.78 ± 3.22 au respectively, p ≤ 0.01). In addition, tissue saturation index was also reduced in the double-leg hypoxic condition (60.2 ± 3.1%) compared to double-leg normoxic (66.0 ± 2.4%, p = 0.008) and single-leg hypoxic (63.3 ± 3.2, p < 0.001) conditions. These data indicate that while at altitude, use of reduced muscle mass exercise can help offset the reduction in tissue oxygenation observed during larger muscle mass activities allowing athletes to exercise at greater limb/muscle specific intensities.
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Affiliation(s)
- Shane Draper
- Department of Exercise Science and Outdoor Recreation, Utah Valley University, Orem, UT 84058, USA;
| | - Tyler Singer
- Department of Exercise Science, Fairmont State University, Fairmont, WV 26554, USA;
| | - Cody Dulaney
- Department of Fitness and Wellness Leadership, State University of New York Plattsburgh, Plattsburgh, NY 12901, USA;
| | - John McDaniel
- Department of Exercise Science, Kent State University, Kent, OH 44242, USA
- Advanced Platform Technology Center, VA Northeast Ohio Healthcare System, Cleveland, OH 44106, USA
- Correspondence:
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8
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Mateo-March M, Muriel X, Valenzuela PL, Gandia-Soriano A, Zabala M, Barranco-Gil D, Pallarés JG, Lucia A. Altitude and Endurance Performance in Altitude Natives versus Lowlanders: Insights from Professional Cycling. Med Sci Sports Exerc 2022; 54:1218-1224. [PMID: 35142712 DOI: 10.1249/mss.0000000000002890] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
INTRODUCTION Acute altitude exposure influences exercise performance, although most research, especially regarding altitude natives, comes from laboratory data in nonathletes. PURPOSE We analyzed the influence of altitude on real-world cycling performance in top-level professional cyclists attending to whether they were altitude natives or not. METHODS Thirty-three male cyclists (29 ± 5 yr) were studied and were classified as lowlanders (n = 19) or altitude natives (n = 14) attending to the altitude of their place of birth (431 ± 380 and 2583 ± 334 meters above sea level (m a.s.l.), respectively). Both groups included top 3 finishers (including winners) in the general classification of Grand Tours and major races. Using data from both training and competitions during years 2013-2020 (8 ± 5 seasons per cyclist), we registered participants' mean maximal power (MMP) for efforts lasting 5 s, 30 s, 5 min, and 10 min, respectively, at altitudes ranging from 0-500 to >2000 m a.s.l. RESULTS A significant altitude-MMP interaction effect (two-factor repeated-measures ANOVA) was found in lowlanders (P < 0.001) but not in altitude natives (P = 0.150). In lowlanders, individual performance decreased in a dose-response manner with increasing altitudes compared with sea (or near-sea) level (0-500 m a.s.l.), whereas this trend was much less evident in natives. A significant altitude-MMP-group effect was found (P < 0.001), with nonsignificant (and overall trivial-to-small differences) between lowlanders and altitude natives for any effort duration at altitudes ≤1500 m a.s.l. but with significant differences at higher altitudes (≥1501 m a.s.l.). CONCLUSIONS Acute altitude exposure influences real-world performance differently in low landers and altitude natives, which might confer a competitive advantage to the latter, particularly in races including efforts at >1500 m a.s.l.
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Affiliation(s)
| | - Xabier Muriel
- Human Performance and Sports Science Laboratory, Faculty of Sport Sciences, University of Murcia, Murcia, SPAIN
| | - Pedro L Valenzuela
- Instituto de Investigación Hospital 12 de Octubre (imas12), Grupo de Investigación en Actividad Física y Salud (PaHerg), Madrid, SPAIN
| | - Alexis Gandia-Soriano
- Biophysics and Medical Physics Group (GIFIME), Department of Physiology, University of Valencia, Valencia, SPAIN
| | - Mikel Zabala
- Department of Physical Education & Sport, Faculty of Sport Sciences, University of Granada, Granada, SPAIN
| | | | - Jesús G Pallarés
- Human Performance and Sports Science Laboratory, Faculty of Sport Sciences, University of Murcia, Murcia, SPAIN
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Płoszczyca K, Chalimoniuk M, Przybylska I, Czuba M. Effects of Short-Term Phosphate Loading on Aerobic Capacity under Acute Hypoxia in Cyclists: A Randomized, Placebo-Controlled, Crossover Study. Nutrients 2022; 14:236. [PMID: 35057416 PMCID: PMC8778537 DOI: 10.3390/nu14020236] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 01/01/2022] [Accepted: 01/03/2022] [Indexed: 02/04/2023] Open
Abstract
The aim of this study was to evaluate the effects of sodium phosphate (SP) supplementation on aerobic capacity in hypoxia. Twenty-four trained male cyclists received SP (50 mg·kg-1 of FFM/day) or placebo for six days in a randomized, crossover study, with a three-week washout period between supplementation phases. Before and after each supplementation phase, the subjects performed an incremental exercise test to exhaustion in hypoxia (FiO2 = 16%). Additionally, the levels of 2,3-diphosphoglycerate (2,3-DPG), hypoxia-inducible factor 1 alpha (HIF-1α), inorganic phosphate (Pi), calcium (Ca), parathyroid hormone (PTH) and acid-base balance were determined. The results showed that phosphate loading significantly increased the Pi level by 9.0%, whereas 2,3-DPG levels, hemoglobin oxygen affinity, buffering capacity and myocardial efficiency remained unchanged. The aerobic capacity in hypoxia was not improved following SP. Additionally, our data revealed high inter-individual variability in response to SP. Therefore, the participants were grouped as Responders and Non-Responders. In the Responders, a significant increase in aerobic performance in the range of 3-5% was observed. In conclusion, SP supplementation is not an ergogenic aid for aerobic capacity in hypoxia. However, in certain individuals, some benefits can be expected, but mainly in athletes with less training-induced central and/or peripheral adaptation.
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Affiliation(s)
- Kamila Płoszczyca
- Department of Kinesiology, Institute of Sport, 01-982 Warsaw, Poland
| | - Małgorzata Chalimoniuk
- Department of Physiotherapy, Faculty of Physical Education and Health in Biala Podlaska, Jozef Pilsudski University of Physical Education in Warsaw, 21-500 Biala Podlaska, Poland
| | - Iwona Przybylska
- Department of Physiotherapy, Faculty of Physical Education and Health in Biala Podlaska, Jozef Pilsudski University of Physical Education in Warsaw, 21-500 Biala Podlaska, Poland
| | - Miłosz Czuba
- Department of Kinesiology, Institute of Sport, 01-982 Warsaw, Poland
- Faculty of Rehabilitation, Jozef Pilsudski University of Physical Education in Warsaw, 00-968 Warsaw, Poland
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10
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Poffé C, Robberechts R, Podlogar T, Kusters M, Debevec T, Hespel P. Exogenous ketosis increases blood and muscle oxygenation but not performance during exercise in hypoxia. Am J Physiol Regul Integr Comp Physiol 2021; 321:R844-R857. [PMID: 34668436 DOI: 10.1152/ajpregu.00198.2021] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Available evidence indicates that elevated blood ketones are associated with improved hypoxic tolerance in rodents. From this perspective, we hypothesized that exogenous ketosis by oral intake of the ketone ester (R)-3-hydroxybutyl (R)-3-hydroxybutyrate (KE) may induce beneficial physiological effects during prolonged exercise in acute hypoxia. As we recently demonstrated KE to deplete blood bicarbonate, which per se may alter the physiological response to hypoxia, we evaluated the effect of KE both in the presence and absence of bicarbonate intake (BIC). Fourteen highly trained male cyclists performed a simulated cycling race (RACE) consisting of 3-h intermittent cycling (IMT180') followed by a 15-min time-trial (TT15') and an all-out sprint at 175% of lactate threshold (SPRINT). During RACE, fraction of inspired oxygen ([Formula: see text]) was gradually decreased from 18.6% to 14.5%. Before and during RACE, participants received either 1) 75 g of ketone ester (KE), 2) 300 mg/kg body mass bicarbonate (BIC), 3) KE + BIC, or 4) a control drink in addition to 60 g of carbohydrates/h in a randomized, crossover design. KE counteracted the hypoxia-induced drop in blood ([Formula: see text]) and muscle oxygenation by ∼3%. In contrast, BIC decreased [Formula: see text] by ∼2% without impacting muscle oxygenation. Performance during TT15' and SPRINT were similar between all conditions. In conclusion, KE slightly elevated the degree of blood and muscle oxygenation during prolonged exercise in moderate hypoxia without impacting exercise performance. Our data warrant to further investigate the potential of exogenous ketosis to improve muscular and cerebral oxygenation status, and exercise tolerance in extreme hypoxia.
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Affiliation(s)
- Chiel Poffé
- Exercise Physiology Research Group, Department of Movement Sciences, KU Leuven, Leuven, Belgium
| | - Ruben Robberechts
- Exercise Physiology Research Group, Department of Movement Sciences, KU Leuven, Leuven, Belgium
| | - Tim Podlogar
- Department for Automation, Biocybernetics and Robotics, Jožef Stefan Institute, Ljubljana, Slovenia.,Faculty of Health Sciences, University of Primorska, Izola, Slovenia
| | - Martijn Kusters
- Bakala Academy-Athletic Performance Center, KU Leuven, Leuven, Belgium
| | - Tadej Debevec
- Department for Automation, Biocybernetics and Robotics, Jožef Stefan Institute, Ljubljana, Slovenia.,Faculty of Sport, University of Ljubljana, Ljubljana, Slovenia
| | - Peter Hespel
- Exercise Physiology Research Group, Department of Movement Sciences, KU Leuven, Leuven, Belgium.,Bakala Academy-Athletic Performance Center, KU Leuven, Leuven, Belgium
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11
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Schörkmaier T, Wahl Y, Brinkmann C, Bloch W, Wahl P. No Influence of Nonivamide-nicoboxil on the Peak Power Output in Competitive Sportsmen. Int J Sports Med 2021; 42:1092-1097. [PMID: 33860476 PMCID: PMC8566025 DOI: 10.1055/a-1403-2701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Accepted: 02/16/2021] [Indexed: 11/04/2022]
Abstract
Recent studies have shown that the oxygenated hemoglobin level can be enhanced during rest through the application of nonivamide-nicoboxil cream. However, the effect of nonivamide-nicoboxil cream on oxygenation and endurance performance under hypoxic conditions is unknown. Therefore, the purpose of this study was to investigate the effects of nonivamide-nicoboxil cream on local muscle oxygenation and endurance performance under normoxic and hypoxic conditions. In a cross-over design, 13 athletes (experienced cyclists or triathletes [age: 25.2±3.5 years; VO2max 62.1±7.3 mL·min-1·kg-1]) performed four incremental exercise tests on the cycle ergometer under normoxic or hypoxic conditions, either with nonivamide-nicoboxil or placebo cream. Muscle oxygenation was recorded with near-infrared spectroscopy. Capillary blood samples were taken after each step, and spirometric data were recorded continuously. The application of nonivamide-nicoboxil cream increased muscle oxygenation at rest and during different submaximal workloads as well as during physical exhaustion, irrespective of normoxic or hypoxic conditions. Overall, there were no significant effects of nonivamide-nicoboxil on peak power output, maximal oxygen uptake or lactate concentrations. Muscle oxygenation is significantly higher with the application of nonivamide-nicoboxil cream. However, its application does not increase endurance performance.
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Affiliation(s)
- Theresa Schörkmaier
- Department of Clinical Research, German Centre for Neurodegenerative Diseases, Bonn, Germany
| | - Yvonne Wahl
- Insitute of Exercise Training and Sport Informatics, German Sport University Cologne, Cologne, Germany
| | - Christian Brinkmann
- Department of Preventive and Rehabilitative Sport Medicine, Institute of Cardiovascular Research and Sport Medicine, German Sport University Cologne, Cologne, Germany
| | - Wilhelm Bloch
- The German Research Centre of Elite Sport, German Sport University Cologne, Cologne, Germany
- Department of Molecular and Cellular Sport Medicine, Institute of Cardiology and Sports Medicine, German Sport University Cologne, Cologne, Germany
| | - Patrick Wahl
- The German Research Centre of Elite Sport, German Sport University Cologne, Cologne, Germany
- Department of Molecular and Cellular Sport Medicine, Institute of Cardiology and Sports Medicine, German Sport University Cologne, Cologne, Germany
- Institute of Interdisciplinary Exercise Science and Sports Medicine, Medical School Hamburg, Germany
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Brocherie F, Fischer S, De Larochelambert Q, Meric H, Riera F. Influence of environmental factors on Olympic cross-country mountain bike performance. Temperature (Austin) 2020; 7:149-156. [PMID: 33015242 DOI: 10.1080/23328940.2020.1761577] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
Olympic distance cross-country cycling (XCO) is a discipline subject to wide performance variability due to uncontrollable environmental factors such as altitude, ambient temperature and/or humidity. This study therefore aimed to investigate the impact of environmental factors on XCO performance in under-23 and elite female and male categories.Individual data were collected from Continental Cup, World Cup, World Championship, and Olympics Games for U23 and elite female and male categories from 2009 to 2018. Factors included were race time (range: 55-157 min), average speed (range: 7.6-32.2 km/h), distance (range: 15.2-48.4 km), altitude (range: 50-2680 m), ambient temperature (range 7-41°C), relative and absolute humidity (range: 8-97% and 2.4-25.3 g/m3, respectively), and categories.The analysis represents 10,966 individual data which indicate a continuous progression of the performance for all categories. Principal component analysis reveals that the slowest XCO performance was resulting from high ambient temperature and absolute humidity. Regressions revealed that only altitude (P < 0.0001) have a direct linear negative effect on XCO average speed. A significant negative interaction effect of altitude with absolute humidity (P < 0.0001) on XCO average speed was also found. In addition, the higher the absolute humidity, the higher is the impact of ambient temperature (P < 0.0001) on XCO average speed.While XCO performance progressed over time regardless of the categories, results also indicate that altitude, ambient temperature, and absolute humidity negatively impact XCO performance. Abbreviations LOESS: local estimated scatterplot smoothing; PCA: Principal component analysis; UCI: Union Cycliste Internationale; U23: under-23; VO2max: maximal oxygen uptake; XCO: cross-country cycling.
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Affiliation(s)
- Franck Brocherie
- Laboratory Sport, Expertise and Performance (EA 7370), Research Department, French Institute of Sport (INSEP), Paris, France
| | - Simon Fischer
- Laboratory European Performance Health Altitude (LEPSA; EA 4604), University of Perpignan via Domitia, Font Romeu, France
| | - Quentin De Larochelambert
- Institut De Recherche bioMédicale Et d'Epidémiologie Du Sport (IRMES), French Institute of Sport (INSEP), Paris, France
| | - Henri Meric
- Laboratory European Performance Health Altitude (LEPSA; EA 4604), University of Perpignan via Domitia, Font Romeu, France
| | - Florence Riera
- Laboratory European Performance Health Altitude (LEPSA; EA 4604), University of Perpignan via Domitia, Font Romeu, France
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Pla R, Brocherie F, Le Garrec S, Richalet J. Effectiveness of the hypoxic exercise test to predict altitude illness and performance at moderate altitude in high-level swimmers. Physiol Rep 2020; 8:e14390. [PMID: 32323493 PMCID: PMC7177172 DOI: 10.14814/phy2.14390] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 02/10/2020] [Indexed: 11/24/2022] Open
Abstract
PURPOSE The hypoxic exercise test is used to predict the susceptibility to severe High Altitude Illness (SHAI). In the present study, we aimed to use this test to predict the changes in performance and the physiological responses to moderate altitude in elite swimmers. METHODS Eighteen elite swimmers performed a hypoxic exercise test at sea level before a moderate 12-day altitude training camp (1,850 m) to determine if they were susceptible or not to SHAI. A maximal swimming performance test was conducted before (at sea level), during (at 1,850 m), and after (at sea level) the intervention. Arterial oxygen saturation (pulse oximetry), Lake Louise score, and quality of sleep questionnaire were collected every morning. The participants were classified in two groups, those who had a moderate to high risk of SHAI (SHAIscore ≥ 3) and those who had a low risk of SHAI (SHAIscore < 3). RESULTS Seven swimmers presented a high risk of SHAI including three of them with a SHAIscore > 5. Pearson correlations indicated that SHAIscore was strongly correlated with the decrease in swimming performance at altitude (r = .60, p < .01). Arterial oxygen saturation during the hypoxic exercise test was the physiological variable that was best related to performance decrease at altitude (r = .54, p < .05). No differences were observed for Lake Louise score and quality of sleep between swimmers who suffered from SHAI or not (p > .1). CONCLUSION In a population of elite swimmers, the combination of clinical and physiological variables (SHAIscore , oxygen desaturation) estimated the performance decrease at moderate altitude. The hypoxic exercise test could allow coaches and scientists to better determine the individual response of their athletes and manage the altitude acclimatization.
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Affiliation(s)
- Robin Pla
- Laboratoire SportExpertise et PerformanceInstitut National du Sport (INSEP)ParisFrance
- Institut de Recherche Médicale et de bio‐Epidémiologie du Sport (IRMES)ParisFrance
- Fédération Française de Natation (FFN)ClichyFrance
| | - Franck Brocherie
- Laboratoire SportExpertise et PerformanceInstitut National du Sport (INSEP)ParisFrance
| | | | - Jean‐Paul Richalet
- Département MédicalInstitut National du Sport (INSEP)ParisFrance
- UMR INSERM 1272 Hypoxie et poumonUniversité Paris 13BobignyFrance
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Atalağ O, Gotshalk LA, Queen L, Wottlin S. More stress for the eastward travelling student athlete: A preliminary analysis. ISOKINET EXERC SCI 2019. [DOI: 10.3233/ies-192170] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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15
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Mahon RT, Ciarlone GE, Roney NG, Swift JM. Cardiovascular Parameters in a Swine Model of Normobaric Hypoxia Treated With 5-Hydroxymethyl-2-Furfural (5-HMF). Front Physiol 2019; 10:395. [PMID: 31057414 PMCID: PMC6482156 DOI: 10.3389/fphys.2019.00395] [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: 12/28/2018] [Accepted: 03/21/2019] [Indexed: 11/24/2022] Open
Abstract
Introduction: The consequences of low partial pressure of O2 include low arterial O2 saturations (SaO2), low blood O2 content (CaO2), elevated mean pulmonary artery pressure (PAP), and decreased O2 consumption VO2. 5-hydroxymethyl-2-furfural (5-HMF) binds to the N-terminal valine of hemoglobin (HgB) and increases its affinity to O2. We used an instrumented, sedated swine model to study the effect of 5-HMF on cardiovascular parameters during exposure to acute normobaric hypoxia (NH). Methods Twenty-three sedated and instrumented swine were randomly assigned to one of three treatment groups and received equal volume of normal saline (VEH), 20 mg/kg 5-HMF (5-HMF-20) or 40 mg/kg 5-HMF (5-HMF-40). Animals then breathed 10% FiO2 for 120 min. Parameters recorded were Cardiac Output (CO), Mean Arterial Blood Pressure (MAP), Heart Rate (HR), Mean Pulmonary Artery Pressure (PAP), SaO2 and saturation of mixed venous blood (SvO2). The P50 was measured at fixed time intervals prior to and during NH. Results 5-HMF decreased P50. In the first 30 min of NH, treatment with 5-HMF-20 and 5-HMF-40 resulted in a (1) significantly smaller decrement in SaO2 and SvO2, (2) significantly lower HR and CO, and (3) smaller increase in PAP compared to VEH. In the 120 min of NH there was a trend toward improved mortality with 5-HMF treatment. Conclusion 5-HMF treatment decreased P50, improved SaO2, and mitigated increases in PAP in this swine model of NH.
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Affiliation(s)
- Richard Thomas Mahon
- Department of Undersea Medicine, Naval Medical Research Center, Silver Spring, MD, United States
| | - Geoffrey E Ciarlone
- Department of Undersea Medicine, Naval Medical Research Center, Silver Spring, MD, United States
| | - Nicholas G Roney
- Department of Undersea Medicine, Naval Medical Research Center, Silver Spring, MD, United States
| | - Joshua M Swift
- Department of Undersea Medicine, Naval Medical Research Center, Silver Spring, MD, United States
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16
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Mourot L. Limitation of Maximal Heart Rate in Hypoxia: Mechanisms and Clinical Importance. Front Physiol 2018; 9:972. [PMID: 30083108 PMCID: PMC6064954 DOI: 10.3389/fphys.2018.00972] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 07/02/2018] [Indexed: 12/17/2022] Open
Abstract
The use of exercise intervention in hypoxia has grown in popularity amongst patients, with encouraging results compared to similar intervention in normoxia. The prescription of exercise for patients largely rely on heart rate recordings (percentage of maximal heart rate (HRmax) or heart rate reserve). It is known that HRmax decreases with high altitude and the duration of the stay (acclimatization). At an altitude typically chosen for training (2,000-3,500 m) conflicting results have been found. Whether or not this decrease exists or not is of importance since the results of previous studies assessing hypoxic training based on HR may be biased due to improper intensity. By pooling the results of 86 studies, this literature review emphasizes that HRmax decreases progressively with increasing hypoxia. The dose–response is roughly linear and starts at a low altitude, but with large inter-study variabilities. Sex or age does not seem to be a major contributor in the HRmax decline with altitude. Rather, it seems that the greater the reduction in arterial oxygen saturation, the greater the reduction in HRmax, due to an over activity of the parasympathetic nervous system. Only a few studies reported HRmax at sea/low level and altitude with patients. Altogether, due to very different experimental design, it is difficult to draw firm conclusions in these different clinical categories of people. Hence, forthcoming studies in specific groups of patients are required to properly evaluate (1) the HRmax change during acute hypoxia and the contributing factors, and (2) the physiological and clinical effects of exercise training in hypoxia with adequate prescription of exercise training intensity if based on heart rate.
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Affiliation(s)
- Laurent Mourot
- EA 3920 Prognostic Markers and Regulatory Factors of Cardiovascular Diseases and Exercise Performance, Health, Innovation Platform, University of Franche-Comté, Besançon, France.,Tomsk Polytechnic University, Tomsk, Russia
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17
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Best A, Braun B. Using a novel data resource to explore heart rate during mountain and road running. Physiol Rep 2018; 5:5/8/e13256. [PMID: 28424267 PMCID: PMC5408286 DOI: 10.14814/phy2.13256] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 03/23/2017] [Accepted: 03/23/2017] [Indexed: 11/24/2022] Open
Abstract
Online, accessible performance and heart rate data from running competitions are posted publicly or semi‐publicly to social media. We tested the efficacy of one such data resource‐ Strava‐ as a tool in exercise physiology investigations by exploring heart rate differences in mountain racing and road racing running events. Heart rate and GPS pace data were gathered from Strava activities posted by 111 males aged 21–49, from two mountain races (Mt. Washington Road Race and Pike's Peak Ascent) and two road race distances (half marathon and marathon). Variables of interest included race finish time, average heart rate, time to complete the first half (by distance) of the race, time to complete the second half, average heart rate for both the first and second half, estimated maximal heart rate, and competitiveness (finish time as percentage of winning time). Mountain runners on average showed no change in heart rate in the second versus first half of the event, while road racers at the half marathon and marathon distances showed increased second‐half heart rate. Mountain runners slowed considerably more in the second half than road runners. Heart rate increases in road races were likely reflective of cardiac drift. Altitude and other demands specific to mountain racing may explain why this was not observed in mountain races. Strava presents enormous untapped opportunity for exercise physiology research, enabling initial inquiry into physiological questions that may then be followed by targeted laboratory studies.
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Affiliation(s)
- Andrew Best
- Department of Anthropology, University of Massachusetts, Amherst, Massachusetts
| | - Barry Braun
- Department of Health and Exercise Science, Colorado State University, Fort Collins, Colorado
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18
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Deb SK, Brown DR, Gough LA, Mclellan CP, Swinton PA, Andy Sparks S, Mcnaughton LR. Quantifying the effects of acute hypoxic exposure on exercise performance and capacity: A systematic review and meta-regression. Eur J Sport Sci 2017; 18:243-256. [PMID: 29220311 DOI: 10.1080/17461391.2017.1410233] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
OBJECTIVE To quantify the effects of acute hypoxic exposure on exercise capacity and performance, which includes continuous and intermittent forms of exercise. DESIGN A systematic review was conducted with a three-level mixed effects meta-regression. The ratio of means method was used to evaluate main effects and moderators providing practical interpretations with percentage change. DATA SOURCES A systemic search was performed using three databases (Google scholar, PubMed and SPORTDiscus). Eligibility criteria for selecting studies: Inclusion was restricted to investigations that assessed exercise performance (time trials (TTs), sprint and intermittent exercise tests) and capacity (time to exhaustion test, TTE) with acute hypoxic (<24 h) exposure and a normoxic comparator. RESULTS Eighty-two outcomes from 53 studies (N = 798) were included in this review. The results show an overall reduction in exercise performance/capacity -17.8 ± 3.9% (95% CI -22.8% to -11.0%), which was significantly moderated by -6.5 ± 0.9% per 1000 m altitude elevation (95% CI -8.2% to -4.8%) and oxygen saturation (-2.0 ± 0.4%; 95% CI -2.9% to -1.2%). TT (-16.2 ± 4.3%; 95% CI -22.9% to -9%) and TTE (-44.5 ± 6.9%; 95% CI -51.3% to -36.7%) elicited a negative effect, whilst indicating a quadratic relationship between hypoxic magnitude and both TTE and TT performance. Furthermore, exercise less than 2 min exhibited no ergolytic effect from acute hypoxia. Summary/Conclusion: This review highlights the ergolytic effect of acute hypoxic exposure, which is curvilinear for TTE and TT performance with increasing hypoxic levels, but short duration intermittent and sprint exercise seem to be unaffected.
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Affiliation(s)
- Sanjoy K Deb
- a Sports Nutriton and Performance Research Group, Department of Sport and Physical Activity , Edge Hill University , Ormskirk , UK
| | - Daniel R Brown
- a Sports Nutriton and Performance Research Group, Department of Sport and Physical Activity , Edge Hill University , Ormskirk , UK
| | - Lewis A Gough
- a Sports Nutriton and Performance Research Group, Department of Sport and Physical Activity , Edge Hill University , Ormskirk , UK
| | | | - Paul A Swinton
- c School of Health Sciences , Robert Gordon University , Aberdeen , UK
| | - S Andy Sparks
- a Sports Nutriton and Performance Research Group, Department of Sport and Physical Activity , Edge Hill University , Ormskirk , UK
| | - Lars R Mcnaughton
- a Sports Nutriton and Performance Research Group, Department of Sport and Physical Activity , Edge Hill University , Ormskirk , UK.,d Department of Sport and Movement Studies, Faculty of Health Science , University of Johannesburg , Johannesburg , South Africa
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Wonnabussapawich P, Hamlin MJ, Lizamore CA, Manimmanakorn N, Leelayuwat N, Tunkamnerdthai O, Thuwakum W, Manimmanakorn A. Living and Training at 825 m for 8 Weeks Supplemented With Intermittent Hypoxic Training at 3,000 m Improves Blood Parameters and Running Performance. J Strength Cond Res 2017; 31:3287-3294. [DOI: 10.1519/jsc.0000000000002227] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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20
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Messier FM, Le Moyec L, Santi C, Gaston AF, Triba MN, Roca E, Durand F. The impact of moderate altitude on exercise metabolism in recreational sportsmen: a nuclear magnetic resonance metabolomic approach. Appl Physiol Nutr Metab 2017; 42:1135-1141. [PMID: 28666093 DOI: 10.1139/apnm-2016-0717] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Although it is known that altitude impairs performance in endurance sports, there is no consensus on the involvement of energy substrates in this process. The objective of the present study was to determine whether the metabolomic pathways used during endurance exercise differ according to whether the effort is performed at sea level or at moderate altitude (at the same exercise intensity, using proton nuclear magnetic resonance, 1H NMR). Twenty subjects performed two 60-min endurance exercise tests at sea level and at 2150 m at identical relative intensity on a cycle ergometer. Blood plasma was obtained from venous blood samples drawn before and after exercise. 1H NMR spectral analysis was then performed on the plasma samples. A multivariate statistical technique was applied to the NMR data. The respective relative intensities of the sea level and altitude endurance tests were essentially the same when expressed as a percentage of the maximal oxygen uptake measured during the corresponding incremental maximal exercise test. Lipid use was similar at sea level and at altitude. In the plasma, levels of glucose, glutamine, alanine, and branched-chain amino acids had decreased after exercise at altitude but not after exercise at sea level. The decrease in plasma glucose and free amino acid levels observed after exercise at altitude indicated that increased involvement of the protein pathway was necessary but not sufficient for the maintenance of glycaemia. Metabolomics is a powerful means of gaining insight into the metabolic changes induced by exercise at altitude.
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Affiliation(s)
- Florian M Messier
- a Laboratoire Européen Performance Santé Altitude EA4604 - Université de Perpignan Via Domitia, Département STAPS, 7 Avenue Pierre de Coubertin, Font-Romeu, France
| | - Laurence Le Moyec
- b Unité de Biologie Intégrative et Adaptation à l'Exercice, EA 7362, Université d'Evry Val D'Essonne, Evry, France
| | - Carole Santi
- a Laboratoire Européen Performance Santé Altitude EA4604 - Université de Perpignan Via Domitia, Département STAPS, 7 Avenue Pierre de Coubertin, Font-Romeu, France
| | - Anne-Fleur Gaston
- a Laboratoire Européen Performance Santé Altitude EA4604 - Université de Perpignan Via Domitia, Département STAPS, 7 Avenue Pierre de Coubertin, Font-Romeu, France
| | - Mohamed N Triba
- c Chimie Structures Propriétés de Biomatériaux et d'Agents Thérapeutiques, CNRS UMR 7244, Université Paris 13 Sorbonne Paris Cité, Bobigny, France
| | - Emma Roca
- a Laboratoire Européen Performance Santé Altitude EA4604 - Université de Perpignan Via Domitia, Département STAPS, 7 Avenue Pierre de Coubertin, Font-Romeu, France.,d Facultat de Medicina, Universitat de Girona, C/Emili Grahit 77, Girona, Spain
| | - Fabienne Durand
- a Laboratoire Européen Performance Santé Altitude EA4604 - Université de Perpignan Via Domitia, Département STAPS, 7 Avenue Pierre de Coubertin, Font-Romeu, France
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Sweeting AJ, Billaut F, Varley MC, Rodriguez RF, Hopkins WG, Aughey RJ. Variations in Hypoxia Impairs Muscle Oxygenation and Performance during Simulated Team-Sport Running. Front Physiol 2017; 8:80. [PMID: 28239359 PMCID: PMC5301029 DOI: 10.3389/fphys.2017.00080] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 01/27/2017] [Indexed: 11/13/2022] Open
Abstract
Purpose: To quantify the effect of acute hypoxia on muscle oxygenation and power during simulated team-sport running. Methods: Seven individuals performed repeated and single sprint efforts, embedded in a simulated team-sport running protocol, on a non-motorized treadmill in normoxia (sea-level), and acute normobaric hypoxia (simulated altitudes of 2,000 and 3,000 m). Mean and peak power was quantified during all sprints and repeated sprints. Mean total work, heart rate, blood oxygen saturation, and quadriceps muscle deoxyhaemoglobin concentration (assessed via near-infrared spectroscopy) were measured over the entire protocol. A linear mixed model was used to estimate performance and physiological effects across each half of the protocol. Changes were expressed in standardized units for assessment of magnitude. Uncertainty in the changes was expressed as a 90% confidence interval and interpreted via non-clinical magnitude-based inference. Results: Mean total work was reduced at 2,000 m (-10%, 90% confidence limits ±6%) and 3,000 m (-15%, ±5%) compared with sea-level. Mean heart rate was reduced at 3,000 m compared with 2,000 m (-3, ±3 min-1) and sea-level (-3, ±3 min-1). Blood oxygen saturation was lower at 2,000 m (-8, ±3%) and 3,000 m (-15, ±2%) compared with sea-level. Sprint mean power across the entire protocol was reduced at 3,000 m compared with 2,000 m (-12%, ±3%) and sea-level (-14%, ±4%). In the second half of the protocol, sprint mean power was reduced at 3,000 m compared to 2,000 m (-6%, ±4%). Sprint mean peak power across the entire protocol was lowered at 2,000 m (-10%, ±6%) and 3,000 m (-16%, ±6%) compared with sea-level. During repeated sprints, mean peak power was lower at 2,000 m (-8%, ±7%) and 3,000 m (-8%, ±7%) compared with sea-level. In the second half of the protocol, repeated sprint mean power was reduced at 3,000 m compared to 2,000 m (-7%, ±5%) and sea-level (-9%, ±5%). Quadriceps muscle deoxyhaemoglobin concentration was lowered at 3,000 m compared to 2,000 m (-10, ±12%) and sea-level (-11, ±12%). Conclusions: Simulated team-sport running is impaired at 3,000 m compared to 2,000 m and sea-level, likely due to a higher muscle deoxygenation.
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Affiliation(s)
- Alice J Sweeting
- Institute of Sport, Exercise and Active Living, Victoria University Melbourne, VIC, Australia
| | - François Billaut
- Institute of Sport, Exercise and Active Living, Victoria UniversityMelbourne, VIC, Australia; Département de Kinesiology, Université LavalQuébec, QC, Canada
| | - Matthew C Varley
- Institute of Sport, Exercise and Active Living, Victoria University Melbourne, VIC, Australia
| | - Ramón F Rodriguez
- Institute of Sport, Exercise and Active Living, Victoria University Melbourne, VIC, Australia
| | - William G Hopkins
- Institute of Sport, Exercise and Active Living, Victoria University Melbourne, VIC, Australia
| | - Robert J Aughey
- Institute of Sport, Exercise and Active Living, Victoria University Melbourne, VIC, Australia
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22
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Peoples GE, McLennan PL. Dietary fish oil delays hypoxic skeletal muscle fatigue and enhances caffeine-stimulated contractile recovery in the rat in vivo hindlimb. Appl Physiol Nutr Metab 2017; 42:613-620. [PMID: 28177707 DOI: 10.1139/apnm-2016-0501] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Oxygen efficiency influences skeletal muscle contractile function during physiological hypoxia. Dietary fish oil, providing docosahexaenoic acid (DHA), reduces the oxygen cost of muscle contraction. This study used an autologous perfused rat hindlimb model to examine the effects of a fish oil diet on skeletal muscle fatigue during an acute hypoxic challenge. Male Wistar rats were fed a diet rich in saturated fat (SF), long-chain (LC) n-6 polyunsaturated fatty acids (n-6 PUFA), or LC n-3 PUFA DHA from fish oil (FO) (8 weeks). During anaesthetised and ventilated conditions (normoxia 21% O2 (SaO2-98%) and hypoxia 14% O2 (SaO2-89%)) the hindlimb was perfused at a constant flow and the gastrocnemius-plantaris-soleus muscle bundle was stimulated via sciatic nerve (2 Hz, 6-12V, 0.05 ms) to established fatigue. Caffeine (2.5, 5, 10 mM) was supplied to the contracting muscle bundle via the arterial cannula to assess force recovery. Hypoxia, independent of diet, attenuated maximal twitch tension (normoxia: 82 ± 8; hypoxia: 41 ± 2 g·g-1 tissue w.w.). However, rats fed FO sustained higher peak twitch tension compared with the SF and n-6 PUFA groups (P < 0.05), and the time to decline to 50% of maximum twitch tension was extended (SF: 546 ± 58; n-6 PUFA: 522 ± 58; FO: 792 ± 96 s; P < 0.05). In addition, caffeine-stimulated skeletal muscle contractile recovery was enhanced in the FO-fed animals (SF: 41 ± 3; n-6 PUFA: 40 ± 4; FO: 52 ± 7% recovery; P < 0.05). These results support a physiological role of DHA in skeletal muscle membranes when exposed to low-oxygen stress that is consistent with the attenuation of muscle fatigue under physiologically normoxic conditions.
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Affiliation(s)
- Gregory E Peoples
- School of Medicine, University of Wollongong, Wollongong, 2522, NSW, Australia.,School of Medicine, University of Wollongong, Wollongong, 2522, NSW, Australia
| | - Peter L McLennan
- School of Medicine, University of Wollongong, Wollongong, 2522, NSW, Australia.,School of Medicine, University of Wollongong, Wollongong, 2522, NSW, Australia
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Beidleman BA, Fulco CS, Buller MJ, Andrew SP, Staab JE, Muza SR. Quantitative Model of Sustained Physical Task Duration at Varying Altitudes. Med Sci Sports Exerc 2016; 48:323-30. [PMID: 26339725 DOI: 10.1249/mss.0000000000000768] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE The objective of this study is to develop a quantitative model that can be used before ascent to altitude (ALT) to predict how much longer a sustained physical task would take for unacclimatized individuals in the early hours of exposure. METHODS Using multiple linear regression, we analyzed time-trial (TT) performance on 95 unacclimatized men (n = 83) and women (n = 12) at sea level (SL) and at an ALT ranging from 2500 to 4300 m. The TT was initiated within 4 h of ascent to ALT. The independent variables known before ascent were as follows: ALT, age, height, weight, sex, SL peak oxygen uptake, SL task duration time, and body mass index (BMI) classification (normal weight vs overweight). The dependent variable was the percent increase in TT duration from SL to ALT. RESULTS The most significant factor in the model was ALT (P = 0.0001), followed by BMI classification (P = 0.0009) and the interaction between BMI classification and ALT (P = 0.003). The model is as follows: percent increase in TT duration = [100 + e(-1.517+1.323 (ALT)+3.124 (BMI class)-0.769 (ALT) (BMI class)]. The percent increase in TT duration in overweight individuals was 129% greater than for normal-weight individuals at 3000 m. However, as ALT increased beyond 3000 m, the disparity between groups decreased until 4050 m where the percent increase in TT duration became greater for normal-weight individuals. CONCLUSIONS This model provides the first quantitative estimates of the percent increase in sustained physical task duration during initial exposure to a wide range of elevations. Because only two easily obtainable factors are required as inputs for the model (ALT and BMI classification), this model can be used by many unacclimatized individuals to better plan their activities at ALT.
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Affiliation(s)
- Beth A Beidleman
- 1Thermal and Mountain Medicine Division, United States Army Research Institute of Environmental Medicine, Natick, MA; and 2Biophysics and Biomedical Modelling Division, United States Army Research Institute of Environmental Medicine, Natick, MA
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George TM, Olsen PD, Kimber NE, Shearman JP, Hamilton JG, Hamlin MJ. The Effect of Altitude and Travel on Rugby Union Performance: Analysis of the 2012 Super Rugby Competition. J Strength Cond Res 2016; 29:3360-6. [PMID: 26595129 DOI: 10.1519/jsc.0000000000001204] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The aim of this study was to investigate whether playing rugby at altitude or after travel (domestic and international) disadvantaged teams. In a retrospective longitudinal study, all matches (N = 125) played in the 2012 Super Rugby Competition were analyzed for key performance indicators (KPI) from coded game data provided by OPTA sports data company. Matches were played in a home-away format in New Zealand, South Africa, and Australia. Teams based at sea level but playing at altitude (1,271-1,753 m) were more likely to miss tackles (mean ± 90% confidence interval, 1.4 ± 1.7) and score fewer points in the first half compared with games at sea level. In the second half of games, sea level teams at altitude were very likely to make fewer gain lines (-4.0 ± 2.7) compared with the second half of games at sea level. The decreased ability to break the defensive line, which may be the result of altitude-induced fatigue, could reduce the likelihood of scoring points and winning a game. Travel also had an effect on KPI, where international travel resulted in more missed tackles (1.7 ± 1.3) and less frequent gain lines (-3.0 ± 1.9) in the first half relative to matches at home; overall, away teams (domestic and international) scored 4 less points in the second half compared with home teams. In conclusion, playing away from home in another country, particularly at altitude, can have a detrimental effect on KPI, which may affect the overall performance and the chances of winning matches.
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Affiliation(s)
- Tina M George
- 1Department of Applied Sciences and Allied Health, Christchurch Polytechnic Institute of Technology, Christchurch, New Zealand; 2Canterbury Rugby Football Union and Crusaders, Christchurch, New Zealand; and 3Department of Tourism, Sport and Society, Lincoln University, Christchurch, New Zealand
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Roberts D, Gebhardt DL, Gaskill SE, Roy TC, Sharp MA. Current considerations related to physiological differences between the sexes and physical employment standards. Appl Physiol Nutr Metab 2016; 41:S108-20. [DOI: 10.1139/apnm-2015-0540] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The use of physical employment standards (PES) has helped ensure that workers have the physical attributes necessary to complete their jobs in a safe and efficient manner. However, PES used in the selection processes have not always reflected the critical physical requirements of the job tasks. Women generally have smaller anthropometric stature than men, less muscle mass, and therefore less strength, power, and endurance, particularly in the upper body. Nonetheless, these attributes in themselves are not valid grounds for exclusion from employment in physically demanding occupations. Selection standards based upon size or strength, irrespective of the job requirements, have resulted in the barring of capable women from physically demanding jobs, claims of gender bias, and costly litigations. To ensure all individuals are provided with equal access to employment, accurate characterization of the critical physical requirements of the job is paramount. This paper summarizes the existing research related to disparities between the sexes that contribute to sex differences in job performance in physically demanding occupations including physical and legal factors. Strategies for mitigating these differences in the setting of PES and the meeting of minimum employment standards are discussed. Where available, injury rates for women and men in physically demanding occupations are presented and the etiology considered. Finally, areas for further research are identified.
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Affiliation(s)
- Delia Roberts
- Fellow of the American College of Sports Medicine (FACSM), School of University Arts and Sciences, Selkirk College, 2808 9th Ave., Castlegar, BC VIN 2Z1, Canada
| | - Deborah L. Gebhardt
- Human Performance Systems Inc., 5000 Sunnyside Avenue, Suite 203, Beltsville, MD 20705, USA
| | - Steven E. Gaskill
- Health and Human Performance Department – Exercise Science, The University of Montana, Missoula, MT 59812, USA
| | - Tanja C. Roy
- Epidemiology and Disease Surveillance, US Army Public Health Command, Blackhawk Rd., Aberdeen Proving Ground, MD 21010, USA
| | - Marilyn A. Sharp
- Military Performance Division, US Army Research Institute of Environmental Medicine, 42 General Green Ave., Natick, MA 01760-5007, USA
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Townsend NE, Gore CJ, Ebert TR, Martin DT, Hahn AG, Chow CM. Ventilatory acclimatisation is beneficial for high-intensity exercise at altitude in elite cyclists. Eur J Sport Sci 2016; 16:895-902. [PMID: 26894371 DOI: 10.1080/17461391.2016.1139190] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
AIM The aim of this study was to examine the relationship between ventilatory adaptation and performance during altitude training at 2700 m. METHODS Seven elite cyclists (age: 21.2 ± 1.1 yr, body mass: 69.9 ± 5.6 kg, height 176.3 ± 4.9 cm) participated in this study. A hypoxic ventilatory response (HVR) test and a submaximal exercise test were performed at sea level prior to the training camp and again after 15 d at altitude (ALT15). Ventilation (VE), end-tidal carbon-dioxide partial pressure (PETCO2) and oxyhaemoglobin saturation via pulse oximetry (SpO2) were measured at rest and during submaximal cycling at 250 W. A hill climb (HC) performance test was conducted at sea level and after 14 d at altitude (ALT14) using a road of similar length (5.5-6 km) and gradient (4.8-5.3%). Power output was measured using SRM cranks. Average HC power at ALT14 was normalised to sea level power (HC%). Multiple regression was used to identify significant predictors of performance at altitude. RESULTS At ALT15, there was a significant increase in resting VE (10.3 ± 1.9 vs. 12.2 ± 2.4 L·min(-1)) and HVR (0.34 ± 0.24 vs. 0.71 ± 0.49 L·min(-1)·%(-1)), while PETCO2 (38.4 ± 2.3 vs. 32.1 ± 3.3 mmHg) and SpO2 (97.9 ± 0.7 vs. 94.0 ± 1.7%) were reduced (P < .05). Multiple regression revealed ΔHVR and exercise VE at altitude as significant predictors of HC% (adjusted r(2) = 0.913; P = 0.003). CONCLUSIONS Ventilatory acclimatisation occurred during a 2 wk altitude training camp in elite cyclists and a higher HVR was associated with better performance at altitude, relative to sea level. These results suggest that ventilatory acclimatisation is beneficial for cycling performance at altitude.
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Affiliation(s)
- Nathan E Townsend
- a Athlete Health and Performance Research Centre , Aspetar Orthopaedic and Sports Medicine Hospital , Doha , Qatar.,b School of Exercise and Nutrition Sciences, Deakin University , Burwood , Australia
| | - Christopher J Gore
- c Department of Physiology , Australian Institute of Sport , Canberra , Australia
| | - Tammie R Ebert
- c Department of Physiology , Australian Institute of Sport , Canberra , Australia
| | - David T Martin
- c Department of Physiology , Australian Institute of Sport , Canberra , Australia
| | - Allan G Hahn
- c Department of Physiology , Australian Institute of Sport , Canberra , Australia
| | - Chin-Moi Chow
- d School of Exercise and Sport Science, University of Sydney , Lidcombe , Australia
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Wehrlin JP, Marti B, Hallén J. Hemoglobin Mass and Aerobic Performance at Moderate Altitude in Elite Athletes. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 903:357-74. [PMID: 27343108 DOI: 10.1007/978-1-4899-7678-9_24] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Fore more than a decade, the live high-train low (LHTL) approach, developed by Levine and Stray-Gundersen, has been widely used by elite endurance athletes. Originally, it was pointed out, that by living at moderate altitude, athletes should benefit from an increased red cell volume (RCV) and hemoglobin mass (Hbmass), while the training at low altitudes should prevent the disadvantage of reduced training intensity at moderate altitude. VO2max is reduced linearly by about 6-8 % per 1000 m increasing altitude in elite athletes from sea level to 3000 m, with corresponding higher relative training intensities for the same absolute work load. With 2 weeks of acclimatization, this initial deficit can be reduced by about one half. It has been debated during the last years whether sea-level training or exposure to moderate altitude increases RCV and Hbmass in elite endurance athletes. Studies which directly measured Hbmass with the optimized CO-rebreathing technique demonstrated that Hbmass in endurance athletes is not influenced by sea-level training. We documented that Hbmass is not increased after 3 years of training in national team cross-country skiers. When athletes are exposed to moderate altitude, new studies support the argument that it is possible to increase Hbmass temporarily by 5-6 %, provided that athletes spend >400 h at altitudes above 2300-2500 m. However, this effect size is smaller than the reported 10-14 % higher Hbmass values of endurance athletes living permanently at 2600 m. It remains to be investigated whether endurance athletes reach these values with a series of LHTL camps.
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Affiliation(s)
- Jon Peter Wehrlin
- Swiss Federal Institute of Sport, Magglingen, Switzerland. .,Norwegian School of Sport Sciences, Oslo, Norway.
| | - Bernard Marti
- Swiss Federal Institute of Sport, Magglingen, Switzerland
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Drain J, Billing D, Neesham-Smith D, Aisbett B. Predicting physiological capacity of human load carriage - a review. APPLIED ERGONOMICS 2016; 52:85-94. [PMID: 26360198 DOI: 10.1016/j.apergo.2015.07.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Revised: 06/07/2015] [Accepted: 07/07/2015] [Indexed: 06/05/2023]
Abstract
This review article aims to evaluate a proposed maximum acceptable work duration model for load carriage tasks. It is contended that this concept has particular relevance to physically demanding occupations such as military and firefighting. Personnel in these occupations are often required to perform very physically demanding tasks, over varying time periods, often involving load carriage. Previous research has investigated concepts related to physiological workload limits in occupational settings (e.g. industrial). Evidence suggests however, that existing (unloaded) workload guidelines are not appropriate for load carriage tasks. The utility of this model warrants further work to enable prediction of load carriage durations across a range of functional workloads for physically demanding occupations. If the maximum duration for which personnel can physiologically sustain a load carriage task could be accurately predicted, commanders and supervisors could better plan for and manage tasks to ensure operational imperatives were met whilst minimising health risks for their workers.
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Affiliation(s)
- Jace Drain
- Land Division, Defence Science and Technology Organisation, 506 Lorimer Street, Fishermans Bend, 3207, Australia.
| | - Daniel Billing
- Land Division, Defence Science and Technology Organisation, 506 Lorimer Street, Fishermans Bend, 3207, Australia
| | - Daniel Neesham-Smith
- Centre for Exercise and Sports Science, School of Exercise and Nutrition Sciences, Deakin University, 221 Burwood Highway, Burwood, 3125, Australia
| | - Brad Aisbett
- Centre for Exercise and Sports Science, School of Exercise and Nutrition Sciences, Deakin University, 221 Burwood Highway, Burwood, 3125, Australia
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Garvican-Lewis LA, Clark B, Martin DT, Schumacher YO, McDonald W, Stephens B, Ma F, Thompson KG, Gore CJ, Menaspà P. Impact of Altitude on Power Output during Cycling Stage Racing. PLoS One 2015; 10:e0143028. [PMID: 26629912 PMCID: PMC4668098 DOI: 10.1371/journal.pone.0143028] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 10/29/2015] [Indexed: 11/18/2022] Open
Abstract
PURPOSE The purpose of this study was to quantify the effects of moderate-high altitude on power output, cadence, speed and heart rate during a multi-day cycling tour. METHODS Power output, heart rate, speed and cadence were collected from elite male road cyclists during maximal efforts of 5, 15, 30, 60, 240 and 600 s. The efforts were completed in a laboratory power-profile assessment, and spontaneously during a cycling race simulation near sea-level and an international cycling race at moderate-high altitude. Matched data from the laboratory power-profile and the highest maximal mean power output (MMP) and corresponding speed and heart rate recorded during the cycling race simulation and cycling race at moderate-high altitude were compared using paired t-tests. Additionally, all MMP and corresponding speeds and heart rates were binned per 1000 m (<1000 m, 1000-2000, 2000-3000 and >3000 m) according to the average altitude of each ride. Mixed linear modelling was used to compare cycling performance data from each altitude bin. RESULTS Power output was similar between the laboratory power-profile and the race simulation, however MMPs for 5-600 s and 15, 60, 240 and 600 s were lower (p ≤ 0.005) during the race at altitude compared with the laboratory power-profile and race simulation, respectively. Furthermore, peak power output and all MMPs were lower (≥ 11.7%, p ≤ 0.001) while racing >3000 m compared with rides completed near sea-level. However, speed associated with MMP 60 and 240 s was greater (p < 0.001) during racing at moderate-high altitude compared with the race simulation near sea-level. CONCLUSION A reduction in oxygen availability as altitude increases leads to attenuation of cycling power output during competition. Decrement in cycling power output at altitude does not seem to affect speed which tended to be greater at higher altitudes.
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Affiliation(s)
- Laura A Garvican-Lewis
- Research Institute for Sport and Exercise, University of Canberra, Canberra, Australia
- Physiology, Australian Institute of Sport, Canberra, Australia
- * E-mail:
| | - Bradley Clark
- Research Institute for Sport and Exercise, University of Canberra, Canberra, Australia
- Physiology, Australian Institute of Sport, Canberra, Australia
| | - David T. Martin
- Physiology, Australian Institute of Sport, Canberra, Australia
| | | | | | | | - Fuhai Ma
- Qinghai Institute of Sport Science, Duoba, China
| | - Kevin G. Thompson
- Research Institute for Sport and Exercise, University of Canberra, Canberra, Australia
| | - Christopher J. Gore
- Physiology, Australian Institute of Sport, Canberra, Australia
- Exercise Physiology Laboratory, Flinders University, Adelaide, Australia
| | - Paolo Menaspà
- Physiology, Australian Institute of Sport, Canberra, Australia
- Edith Cowan University, Perth, Australia
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Endurance exercise performance in acute hypoxia is influenced by expiratory flow limitation. Eur J Appl Physiol 2015; 115:1653-63. [DOI: 10.1007/s00421-015-3145-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 02/25/2015] [Indexed: 10/23/2022]
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Abstract
AbstractPurpose. Recreational cross-country skiers can benefit from a performance diagnostic when planning a training program. The aim of this study was to establish a simple test protocol to measure endurance capacity and provide training recommendations. Methods. The relationship between endurance performance and cross-country skiing technique was assessed using two tests. First, a lactate threshold test whereby running speed was determined on a treadmill at 4 mmol/l blood lactate concentration. Second, participants completed a variation of the Cooper test using skating technique on flat terrain to determine the distance covered in 12 min and maximum heart rate. Results. There was a correlative (r = 0.18 respectivelly R2 = 0.43) relationship of between the distance covered in the Cooper test and treadmill running speed at 4 mmol/l blood lactate concentration. Conclusions. The two tests allow recreational athletes to rank themselves with regards to their endurance capacity within a population. The relationship between distance covered and maximum heart rate can indicate whether future training should focus on technical or physical improvement.
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Aughey RJ, Hammond K, Varley MC, Schmidt WF, Bourdon PC, Buchheit M, Simpson B, Garvican-Lewis LA, Kley M, Soria R, Sargent C, Roach GD, Claros JCJ, Wachsmuth N, Gore CJ. Soccer activity profile of altitude versus sea-level natives during acclimatisation to 3600 m (ISA3600). Br J Sports Med 2013; 47 Suppl 1:i107-13. [PMID: 24282196 PMCID: PMC3903145 DOI: 10.1136/bjsports-2013-092776] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/10/2013] [Indexed: 11/15/2022]
Abstract
OBJECTIVES We investigated the effect of high altitude on the match activity profile of elite youth high altitude and sea level residents. METHODS Twenty Sea Level (Australian) and 19 Altitude-resident (Bolivian) soccer players played five games, two near sea level (430 m) and three in La Paz (3600 m). Match activity profile was quantified via global positioning system with the peak 5 min period for distance ((D₅(peak)) and high velocity running (>4.17 m/s, HIVR₅(peak)); as well as the 5 min period immediately subsequent to the peak for both distance (D₅(sub)) and high-velocity running (HIVR₅(sub)) identified using a rolling 5 min epoch. The games at 3600 m were compared with the average of the two near sea-level games. RESULTS The total distance per minute was reduced by a small magnitude in the first match at altitude in both teams, without any change in low-velocity running. There were variable changes in HiVR, D₅(peak) and HiVR₅(peak) from match to match for each team. There were within-team reductions in D₅(peak) in each game at altitude compared with those at near sea level, and this reduction was greater by a small magnitude in Australians than Bolivians in game 4. The effect of altitude on HiVR₅(peak) was moderately lower in Australians compared with Bolivians in game 3. There was no clear difference in the effect of altitude on maximal accelerations between teams. CONCLUSIONS High altitude reduces the distance covered by elite youth soccer players during matches. Neither 13 days of acclimatisation nor lifelong residence at high altitude protects against detrimental effects of altitude on match activity profile.
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Affiliation(s)
- Robert J Aughey
- Institute of Sport, Exercise and Active Living, College of Sport and Exercise Science, Victoria University, Melbourne, Australia
- Western Bulldogs Football Club, Melbourne, Australia
| | - Kristal Hammond
- Institute of Sport, Exercise and Active Living, College of Sport and Exercise Science, Victoria University, Melbourne, Australia
| | - Matthew C Varley
- Institute of Sport, Exercise and Active Living, College of Sport and Exercise Science, Victoria University, Melbourne, Australia
| | - Walter F Schmidt
- Department of Sports Medicine/Sports Physiology, University of Bayreuth, Bayreuth, Germany
| | | | | | - Ben Simpson
- ASPIRE Academy for Sports Excellence, Doha, Qatar
| | - Laura A Garvican-Lewis
- National Institute of Sports Studies, University of Canberra, Canberra, Australia
- Department of Physiology, Australian Institute of Sport, Canberra, Australia
| | - Marlen Kley
- Department of Sports Medicine/Sports Physiology, University of Bayreuth, Bayreuth, Germany
| | - Rudy Soria
- Facultad de Medicina, Instituto Boliviano de Biología de Altura (IBBA), Universidad Mayor de San Andrés, La Paz, Bolivia
| | - Charli Sargent
- Appleton Institute, Central Queensland University, Adelaide, Australia
| | - Gregory D Roach
- Appleton Institute, Central Queensland University, Adelaide, Australia
| | - Jesus C Jimenez Claros
- Facultad de Medicina, Instituto Boliviano de Biología de Altura (IBBA), Universidad Mayor de San Andrés, La Paz, Bolivia
| | - Nadine Wachsmuth
- Department of Sports Medicine/Sports Physiology, University of Bayreuth, Bayreuth, Germany
| | - Christopher J Gore
- Department of Physiology, Australian Institute of Sport, Canberra, Australia
- Exercise Physiology Laboratory, Flinders University, Adelaide, Australia
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Nassis GP. Effect of altitude on football performance: analysis of the 2010 FIFA World Cup Data. J Strength Cond Res 2013; 27:703-7. [PMID: 22648134 DOI: 10.1519/jsc.0b013e31825d999d] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Laboratory studies show that altitude ascent impairs endurance performance. Limited data exist on football, and information from official matches is very scarce even for other team sports. The aim of this study was to examine the effect of altitude on football performance during the 2010 World Cup in South Africa. It was hypothesized that (a) total distance covered, an index of endurance, would be reduced above the altitude of 580 m, and (b) technical skills would be affected because altitude alters ball flight characteristics. Physical performance, goals scored, and goalkeepers' errors that resulted in goals conceded were recorded from the official game statistics of Fédération Internationale de Football Association during the South Africa 2010 World Cup. Matches were played at sea level (altitude: 0 m), 660, 1200-1400, and 1401-1753 m. After testing for data normality, mean differences were checked with a one-way analysis of variance. Results show a 3.1% lower total distance that was covered by the teams during the matches played at 1200-1400 and 1401-1753 m (p < 0.05) compared with sea level. Indices of technical skills, including number of goals scored per game and errors made by the goalkeepers that resulted in goals conceded, did not differ with altitude. It is concluded that playing football above 1200 m had negative effects on endurance but not on technical skills during World Cup 2010 matches. It seems that teams should follow several days of acclimatization before playing at altitude as low as 1200 m, to ameliorate the negative effects of altitude on physical performance.
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Affiliation(s)
- George P Nassis
- Department of Sport Medicine and Biology of Exercise, Faculty of Physical Education and Sport Science, National and Kapodistrian University of Athens, Athens, Greece.
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Interaction of central and peripheral factors during repeated sprints at different levels of arterial O2 saturation. PLoS One 2013; 8:e77297. [PMID: 24155938 PMCID: PMC3796493 DOI: 10.1371/journal.pone.0077297] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Accepted: 08/31/2013] [Indexed: 11/19/2022] Open
Abstract
Purpose To investigate the interaction between the development of peripheral locomotor muscle fatigue, muscle recruitment and performance during repeated-sprint exercise (RSE). Method In a single-blind, randomised and cross-over design, ten male team-sport athletes performed two RSE (fifteen 5-s cycling sprints interspersed with 25 s of rest; power self-selected) in normoxia and in acute moderate hypoxia (FIO2 0.138). Mechanical work, total electromyographic intensity (summed quadriceps electromyograms, RMSsum) and muscle (vastus lateralis) and pre-fontal cortex near-infrared spectroscopy (NIRS) parameters were calculated for every sprint. Blood lactate concentration ([Lac-]) was measured throughout the protocol. Peripheral quadriceps fatigue was assessed via changes in potentiated quadriceps twitch force (ΔQtw,pot) pre- versus post-exercise in response to supra-maximal magnetic femoral nerve stimulation. The central activation ratio (QCAR) was used to quantify completeness of quadriceps activation. Results Compared with normoxia, hypoxia reduced arterial oxygen saturation (-13.7%, P=0.001), quadriceps RMSsum (-13.7%, P=0.022), QCAR (-3.3%, P=0.041) and total mechanical work (-8.3%, P=0.019). However, the magnitude of quadriceps fatigue induced by RSE was similar in the two conditions (ΔQtw,pot: -53.5% and -55.1%, P=0.71). The lower cycling performance in hypoxia occurred despite similar metabolic (muscle NIRS parameters and blood [Lac-]) and functional (twitch and M-wave) muscle states. Conclusion Results suggest that the central nervous system regulates quadriceps muscle recruitment and, thereby, performance to limit the development of muscle fatigue during intermittent, short sprints. This finding highlights the complex interaction between muscular perturbations and neural adjustments during sprint exercise, and further supports the presence of pacing during intermittent sprint exercise.
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Lower running performance and exacerbated fatigue in soccer played at 1600 m. Int J Sports Physiol Perform 2013; 9:397-404. [PMID: 23751901 DOI: 10.1123/ijspp.2012-0375] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
PURPOSE This study investigated the decrement in running performance of elite soccer players competing at low altitude and time course for abatement of these decrements. METHODS Twenty elite youth soccer players had their activity profile, in a sea-level (SL) and 2 altitude (Alt, 1600 m, d 4, and d 6) matches, measured with a global positioning system. Measures expressed in meters per minute of match time were total distance, low- and high-velocity running (LoVR, 0.01-4.16 m/s; HiVR, 4.17-10.0 m/s), and frequency of maximal accelerations (>2.78 m/s2). The peak and subsequent stanza for each measure were identified and a transient fatigue index calculated. Mean heart rate (HR) during the final minute of a submaximal running task (5 min, 11 km/h) was recorded at SL and for 10 d at Alt. Differences were determined between SL and Alt using percentage change and effect-size (ES) statistic with 90% confidence intervals. RESULTS Mean HR almost certainly increased on d 1 (5.4%, ES 1.01 ± 0.35) and remained probably elevated on both d 2 (ES 0.42 ± 0.31) and d3 (ES 0.30 ± 0.25), returning to baseline at d 5. Total distance was almost certainly lower than SL (ES -0.76 ± 0.37) at d 4 and remained probably reduced on d 6 (ES -0.42 ± 0.36). HiVR probably decreased at d 4 vs SL (-0.47 ± 0.59), with no clear effect of altitude at d 6 (-0.08 ± 0.41). Transient fatigue in matches was evident at SL and Alt, with a possibly greater decrement at Alt. CONCLUSION Despite some physiological adaptation, match running performance of youth soccer players is compromised for at least 6 d at low altitude.
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Billaut F, Gore CJ, Aughey RJ. Enhancing team-sport athlete performance: is altitude training relevant? Sports Med 2013; 42:751-67. [PMID: 22845561 DOI: 10.1007/bf03262293] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Field-based team sport matches are composed of short, high-intensity efforts, interspersed with intervals of rest or submaximal exercise, repeated over a period of 60-120 minutes. Matches may also be played at moderate altitude where the lower oxygen partial pressure exerts a detrimental effect on performance. To enhance run-based performance, team-sport athletes use varied training strategies focusing on different aspects of team-sport physiology, including aerobic, sprint, repeated-sprint and resistance training. Interestingly, 'altitude' training (i.e. living and/or training in O(2)-reduced environments) has only been empirically employed by athletes and coaches to improve the basic characteristics of speed and endurance necessary to excel in team sports. Hypoxia, as an additional stimulus to training, is typically used by endurance athletes to enhance performance at sea level and to prepare for competition at altitude. Several approaches have evolved in the last few decades, which are known to enhance aerobic power and, thus, endurance performance. Altitude training can also promote an increased anaerobic fitness, and may enhance sprint capacity. Therefore, altitude training may confer potentially-beneficial adaptations to team-sport athletes, which have been overlooked in contemporary sport physiology research. Here, we review the current knowledge on the established benefits of altitude training on physiological systems relevant to team-sport performance, and conclude that current evidence supports implementation of altitude training modalities to enhance match physical performances at both sea level and altitude. We hope that this will guide the practice of many athletes and stimulate future research to better refine training programmes.
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Affiliation(s)
- François Billaut
- School of Sport and Exercise Science, Institute of Sport, Exercise and Active Living (ISEAL), Victoria University, Melbourne, VIC, Australia.
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Leatherwood WE, Dragoo JL. Effect of airline travel on performance: a review of the literature. Br J Sports Med 2012; 47:561-7. [PMID: 23143931 DOI: 10.1136/bjsports-2012-091449] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The need for athletes to travel long distances has spurred investigation into the effect of air travel across multiple time zones on athletic performance. Rapid eastward or westward travel may negatively affect the body in many ways; therefore, strategies should be employed to minimise these effects which may hamper athletic performance. In this review, the fundamentals of circadian rhythm disruption are examined along with additional effects of airline travel including jet lag, sleep deprivation, travel at altitude and nutritional considerations that negatively affect performance. Evidence-based recommendations are provided at the end of the manuscript to minimise the effects of airline travel on performance.
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Affiliation(s)
- Whitney E Leatherwood
- Department of Orthopaedic Surgery, Stanford University, Stanford, California 94063-6342, USA
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Ponsot E, Dufour SP, Doutreleau S, Lonsdorfer-Wolf E, Lampert E, Piquard F, Geny B, Mettauer B, Ventura-Clapier R, Richard R. Impairment of maximal aerobic power with moderate hypoxia in endurance athletes: do skeletal muscle mitochondria play a role? Am J Physiol Regul Integr Comp Physiol 2010; 298:R558-66. [DOI: 10.1152/ajpregu.00216.2009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study investigates the role of central vs. peripheral factors in the limitation of maximal oxygen uptake (V̇o2max) with moderate hypoxia [inspired fraction (FiO2) =14.5%]. Fifteen endurance-trained athletes performed maximal cycle incremental tests to assess V̇o2max, maximal cardiac output (Q̇max), and maximal arteriovenous oxygen (a-vO2) difference in normoxia and hypoxia. Muscle biopsies of vastus lateralis were taken 1 wk before the cycling tests to evaluate maximal muscle oxidative capacity (V̇max) and sensitivity of mitochondrial respiration to ADP ( Km) on permeabilized muscle fibers in situ. Those athletes exhibiting the largest reduction of V̇o2max in moderate hypoxia (Severe Loss group: −18 ± 2%) suffered from significant reductions in Q̇max (−4 ± 1%) and maximal a-vO2 difference (−14 ± 2%). Athletes who well tolerated hypoxia, as attested by a significantly smaller drop of V̇o2max with hypoxia (Moderate Loss group: −7 ± 1%), also display a blunted Q̇max (−9 ± 2%) but, conversely, were able to maintain maximal a-vO2 difference (+1 ± 2%). Though V̇max was similar in the two experimental groups, the smallest reduction of V̇o2max with moderate hypoxia was observed in those athletes presenting the lowest apparent Km for ADP in the presence of creatine ( Km+Cr). In already-trained athletes with high muscular oxidative capacities, the qualitative, rather than quantitative, aspects of the mitochondrial function may constitute a limiting factor to aerobic ATP turnover when exercising at low FiO2, presumably through the functional coupling between the mitochondrial creatine kinase and ATP production. This study suggests a potential role for peripheral factors, including the alteration of cellular homeostasis in active muscles, in determining the tolerance to hypoxia in maximally exercising endurance-trained athletes.
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Affiliation(s)
- Elodie Ponsot
- Service de Physiologie et d'Explorations Fonctionnelles, Hôpital Civil and Département de Physiologie, UPRES E.A. 3072, Faculté de Médecine, Strasbourg, France
- School of Health and Medical Sciences, Örebro University, Örebro, Sweden
| | - Stéphane P. Dufour
- Service de Physiologie et d'Explorations Fonctionnelles, Hôpital Civil and Département de Physiologie, UPRES E.A. 3072, Faculté de Médecine, Strasbourg, France
- UFR STAPS, Université de Strasbourg, Strasbourg, France
| | - Stéphane Doutreleau
- Service de Physiologie et d'Explorations Fonctionnelles, Hôpital Civil and Département de Physiologie, UPRES E.A. 3072, Faculté de Médecine, Strasbourg, France
| | - Evelyne Lonsdorfer-Wolf
- Service de Physiologie et d'Explorations Fonctionnelles, Hôpital Civil and Département de Physiologie, UPRES E.A. 3072, Faculté de Médecine, Strasbourg, France
| | - Eliane Lampert
- Service de Physiologie et d'Explorations Fonctionnelles, Hôpital Civil and Département de Physiologie, UPRES E.A. 3072, Faculté de Médecine, Strasbourg, France
| | - François Piquard
- Service de Physiologie et d'Explorations Fonctionnelles, Hôpital Civil and Département de Physiologie, UPRES E.A. 3072, Faculté de Médecine, Strasbourg, France
| | - Bernard Geny
- Service de Physiologie et d'Explorations Fonctionnelles, Hôpital Civil and Département de Physiologie, UPRES E.A. 3072, Faculté de Médecine, Strasbourg, France
| | - Bertrand Mettauer
- Service de Cardiologie, Hôpitaux Civils de Colmar, Colmar, France; and
| | | | - Ruddy Richard
- Service de Physiologie et d'Explorations Fonctionnelles, Hôpital Civil and Département de Physiologie, UPRES E.A. 3072, Faculté de Médecine, Strasbourg, France
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Martin DS, Levett DZH, Grocott MPW, Montgomery HE. Variation in human performance in the hypoxic mountain environment. Exp Physiol 2010; 95:463-70. [DOI: 10.1113/expphysiol.2009.047589] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Chapman RF, Stickford JL, Levine BD. Altitude training considerations for the winter sport athlete. Exp Physiol 2010; 95:411-21. [DOI: 10.1113/expphysiol.2009.050377] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Levine BD, Stray-Gundersen J, Mehta RD. Effect of altitude on football performance. Scand J Med Sci Sports 2008; 18 Suppl 1:76-84. [PMID: 18665955 DOI: 10.1111/j.1600-0838.2008.00835.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Altitude will impact football performance through two separate and parallel pathways related to the hypobaric (physical) and hypoxic (physiological) components of terrestrial altitude: (a) the decrease in partial pressure of oxygen reduces maximal oxygen uptake and impairs "aerobic" performance by reducing maximal aerobic power, increasing the relative intensity of any given absolute level of work, and delaying recovery of high-energy phosphates between high-intensity "interval" type efforts; (b) the decrease in air density reduces air resistance which will facilitate high-velocity running, but will also alter drag and lift thereby impairing sensorimotor skills. These effects appear to have their greatest impact very early in the altitude exposure, and their physiological/neurosensory consequences are ameliorated by acclimatization, though the extent of restoration of sea level type performance depends on the absolute magnitude of the competing and living altitudes.
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Affiliation(s)
- B D Levine
- Institute For Exercise and Environmental Medicine, Presbyterian Hospital of Dallas, University of Texas Southwestern Medical Center at Dallas, Texas 75231, USA.
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McKenzie DC, Boulet LP. Asthma, outdoor air quality and the Olympic Games. CMAJ 2008; 179:543-8. [PMID: 18687919 DOI: 10.1503/cmaj.080982] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Affiliation(s)
- Donald C McKenzie
- Division of Sports Medicine and School of Human Kinetics, University of British Columbia, Vancouver, BC.
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Bärtsch P, Saltin B. General introduction to altitude adaptation and mountain sickness. Scand J Med Sci Sports 2008; 18 Suppl 1:1-10. [DOI: 10.1111/j.1600-0838.2008.00827.x] [Citation(s) in RCA: 140] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Brothers MD, Hilger K, Carson JM, Sullivan L, Byrnes WC. GXT responses in altitude-acclimatized cyclists during sea-level simulation. Med Sci Sports Exerc 2008; 39:1727-35. [PMID: 17909399 DOI: 10.1249/mss.0b013e3181238a3f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE This study examined the effects of gender on graded exercise stress test (GXT) response in moderate-altitude (MA)-acclimatized cyclists during sea-level (SL) simulation. It was hypothesized that alterations in arterial saturation would relate to changes in VO2peak. METHODS Twenty competitive cyclists (12 males, 8 females) who were residents of MA locations underwent two randomized bicycle GXTs: one under local normoxic hypobaria, and the other under simulated SL conditions. RESULTS Under the SL condition, the cyclists demonstrated a significant increase (2-3%) in absolute and relative VO2peak, improved (4%) economy at lactate threshold (LT), and time-adjusted peak power (7%); the range of improvement between individuals varied from -6% to +25%. Simulated SL also resulted in a greater arterial saturation (S(a)O2) at rest and VO2peak, and significantly less desaturation (4 vs 8%) from rest to VO2peak. The individual variability in the change (Delta) in VO2peak was not significantly correlated to SL S(a)O2 or any other S(a)O2 variable analyzed, regardless of whether we examined each gender individually or combined. Significant correlations were found between Delta-peak power and Delta-economy as well as Delta-VO2peak and Delta-GXT time. These correlations as well as degree of improvement varied by gender. CONCLUSIONS These data suggest that chronic residence at MA may attenuate the occurrence of exercise-induced arterial hypoxemia and eliminate the relationship between S(a)O2 and Delta-VO2peak that has been reported among SL residents acutely exposed to altitude. Additionally, the improvements that occur in predictors of aerobic performance when MA residents are exposed acutely to SL conditions have a large degree of individual variability, and the mechanism(s) for improvement may vary by gender.
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Affiliation(s)
- Michael D Brothers
- Department of Integrative Physiology, University of Colorado, Boulder, CO, USA.
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Clark SA, Bourdon PC, Schmidt W, Singh B, Cable G, Onus KJ, Woolford SM, Stanef T, Gore CJ, Aughey RJ. The effect of acute simulated moderate altitude on power, performance and pacing strategies in well-trained cyclists. Eur J Appl Physiol 2007; 102:45-55. [PMID: 17882451 DOI: 10.1007/s00421-007-0554-0] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/08/2007] [Indexed: 11/26/2022]
Abstract
Athletes regularly compete at 2,000-3,000 m altitude where peak oxygen consumption (VO2peak) declines approximately 10-20%. Factors other than VO2peak including gross efficiency (GE), power output, and pacing are all important for cycling performance. It is therefore imperative to understand how all these factors and not just VO2peak are affected by acute hypobaric hypoxia to select athletes who can compete successfully at these altitudes. Ten well-trained, non-altitude-acclimatised male cyclists and triathletes completed cycling tests at four simulated altitudes (200, 1,200, 2,200, 3,200 m) in a randomised, counter-balanced order. The exercise protocol comprised 5 x 5-min submaximal efforts (50, 100, 150, 200 and 250 W) to determine submaximal VO2 and GE and, after 10-min rest, a 5-min maximal time-trial (5-minTT) to determine VO2peak and mean power output (5-minTT(power)). VO2peak declined 8.2 +/- 2.0, 13.9 +/- 2.9 and 22.5 +/- 3.8% at 1,200, 2,200 and 3,200 m compared with 200 m, respectively, P < 0.05. The corresponding decreases in 5-minTT(power) were 5.8 +/- 2.9, 10.3 +/- 4.3 and 19.8 +/- 3.5% (P < 0.05). GE during the 5-minTT was not different across the four altitudes. There was no change in submaximal VO2 at any of the simulated altitudes, however, submaximal efficiency decreased at 3,200 m compared with both 200 and 1,200 m. Despite substantially reduced power at simulated altitude, there was no difference in pacing at the four altitudes for athletes whose first trial was at 200 or 1,200 m; whereas athletes whose first trial was at 2,200 or 3,200 m tended to mis-pace that effort. In conclusion, during the 5-minTT there was a dose-response effect of hypoxia on both VO2peak and 5-minTT(power) but no effect on GE.
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Affiliation(s)
- Sally A Clark
- Department of Physiology, Australian Institute of Sport, Canberra, ACT, Australia.
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Hamlin MJ, Hinckson EA, Wood MR, Hopkins WG. Simulated rugby performance at 1550-m altitude following adaptation to intermittent normobaric hypoxia. J Sci Med Sport 2007; 11:593-9. [PMID: 17719848 DOI: 10.1016/j.jsams.2007.07.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2006] [Revised: 07/17/2007] [Accepted: 07/17/2007] [Indexed: 11/18/2022]
Abstract
Team-sport athletes who normally reside at sea level occasionally play games at altitudes sufficient to impair endurance performance. To investigate the effect of intermittent normobaric hypoxic exposure on performance in generic and game-specific tests at altitude, 22 senior club level rugby players performed baseline tests before single-blind random assignment to one of three groups: hypoxia-altitude (n=9), normoxia-altitude (n=6), and normoxia-sea level (n=7). The hypoxia-altitude group underwent 9-13 sessions of intermittent hypoxic exposure (concentration of inspired oxygen=13-10%) over 15 days, then repeated the performance tests within 12h of travelling to 1550m. The normoxia-altitude group underwent placebo exposures by breathing room air before repeating the tests at altitude, whereas the normoxia-sea level group underwent placebo exposures before repeating the tests at sea level. Hypoxic exposure consisted of alternately breathing 6min hypoxic gas and 4min ambient air for 1h at rest. Performance measures gathered at each testing session were maximum speed, sub-maximum heart-rate speed and sub-maximum lactate speed during a 20-m incremental running test, mean time in six 70-m sprints, repetitive explosive power and other measures from seven 5.5-min circuits of a rugby simulation. Repetitive explosive power ( approximately -16%) and 20-m shuttle performance ( approximately -3%) decreased substantially at altitude compared to sea level. Acclimatisation to hypoxia had a beneficial effect on sub-maximum heart rate and lactate speed but little effect on other performance measures. In conclusion, 1550-m altitude substantially impaired some measures of performance and the effects of prior adaptation via 9-13 sessions of intermittent hypoxia were mostly unclear.
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Mollard P, Woorons X, Letournel M, Lamberto C, Favret F, Pichon A, Beaudry M, Richalet JP. Determinant factors of the decrease in aerobic performance in moderate acute hypoxia in women endurance athletes. Respir Physiol Neurobiol 2007; 159:178-86. [PMID: 17766196 DOI: 10.1016/j.resp.2007.06.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2007] [Revised: 06/23/2007] [Accepted: 06/23/2007] [Indexed: 11/28/2022]
Abstract
The purpose of this study was to evaluate the limiting factors of maximal aerobic performance in endurance trained (TW) and sedentary (UW) women. Subjects performed four incremental tests on a cycle ergometer at sea level and in normobaric hypoxia corresponding to 1000, 2500 and 4500 m. Maximal oxygen uptake decrement (Delta VO2 max) was larger in TW at each altitude. Maximal heart rate and ventilation decreased at 4500 m in TW. Maximal cardiac output remained unchanged. In both groups, arterialized oxygen saturation (Sa'O2 max) decreased at and above 2500 m and maximal O2 transport (QaO2 max) decreased from 1000 m. At 4500 m, there was no more difference in QaO2 max between TW and UW. Mixed venous O2 pressure (PvO2 max) was lower and O2 extraction (O2ERmax) greater in TW at each altitude. The primary determinant factor of VO2 max decrement in moderate acute hypoxia in trained and untrained women is a reduced maximal O2 transport that cannot be compensate by tissue O2 extraction.
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Affiliation(s)
- Pascal Mollard
- Université Paris 13, Laboratoire Réponses cellulaires et fonctionnelles à l'hypoxie, EA2363, ARPE, 74 rue Marcel Cachin, 93017 Bobigny Cedex, France.
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Abstract
Hypoxia elicits hematopoiesis, which ultimately improves oxygen transport to peripheral tissues. In part because of this, altitude training has been used in the conditioning of elite endurance athletes for decades, despite equivocal evidence that such training benefits subsequent sea level performance. Recently, traditional live high-train high athletic conditioning has been implicated in a number of deleterious effects on training intensity, cardiac output, muscle composition, and fluid and metabolite balance--effects that largely offset hematopoietic benefits during sea level performance. Modified live high-train low conditioning regimens appear to capture the beneficial hematopoietic effects of hypoxic training while avoiding many of the deleterious effects of training at altitude. Because of the logistical and financial barriers to living high and training low, various methods to simulate hypoxia have been developed and studied. The data from these studies suggest a threshold requirement for hypoxic exposure to meaningfully augment hematopoiesis, and presumably improve athletic performance.
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Affiliation(s)
- Brett M Loffredo
- Division of Sports Medicine, Maine Medical Center,Department of Family Medicine, 272 Congress Street,Portland, ME 04101, USA
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Woorons X, Mollard P, Lamberto C, Letournel M, Richalet JP. Effect of acute hypoxia on maximal exercise in trained and sedentary women. Med Sci Sports Exerc 2005; 37:147-54. [PMID: 15632681 DOI: 10.1249/01.mss.0000150020.25153.34] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE The purpose of this study was to determine the physiological responses of sedentary and endurance-trained female subjects during maximal exercise at different levels of acute hypoxia. METHODS Fourteen women who were sea level residents were divided into two groups according to their level of fitness: 1) endurance-trained women (TW) (N = 7), VO(2max) = 56.3 +/- 4.7 mL.kg(-1).min(-1); and 2) sedentary women (SW) (N = 7), VO(2max) = 34.8 +/- 5.6 mL.kg(-1).min(-1). Subjects performed four maximal cycle ergometer tests in normoxia and under hypoxic conditions (F(I)O(2) = 0.187, 0.154, and 0.117, corresponding to altitudes of 1000, 2500, and 4500 m, respectively). RESULTS VO(2max) decreased significantly by 3.6 +/- 2.1, 14 +/- 2.5, and 27.4 +/- 3.6% in TW, and by 5 +/- 4, 9.4 +/- 6.4, and 18.7 +/- 7% in SW at 1000, 2500, and 4500 m, respectively. The drop of VO(2max) (DeltaVO(2max)) was greater in TW at and above 2500 m. Arterial O2 saturation (SpO(2)) at maximal exercise was lower in TW at every altitude (1000 m: 90.9 +/- 1.9 vs 94.6 +/- 1.4%; 2500 m: 82.8 +/- 2.8 vs 90.0 +/- 2.1%; 4500 m: 65.0 +/- 4.7 vs 73.6 +/- 4.5%). Maximal heart rate decreased significantly from 1000 m in the two groups. SpO(2) was correlated to DeltaVO(2max) at 4500 m (r = -0.81, P < 0.01) and 2500 m (r = -0.81, P < 0.01), but not below. Furthermore, we noted a relationship between SpO(2) and O2 pulse (VO(2)/HR) at every F(I)O(2). CONCLUSION These results demonstrate that endurance-trained women show a greater decrement in VO(2max) at high altitudes. This could be explained mainly by a higher arterial desaturation, which is largely caused, according to our results, by diffusion limitation.
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Affiliation(s)
- Xavier Woorons
- Laboratory of Functional and Cellular Responses to Hypoxia, UFR-SMBH Universite Paris, 74 rue Marcel Cachin, 93017 Bobigny Cedex, France.
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