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Cupka M, Sedliak M. Hungry runners - low energy availability in male endurance athletes and its impact on performance and testosterone: mini-review. Eur J Transl Myol 2023. [PMID: 37052052 PMCID: PMC10388605 DOI: 10.4081/ejtm.2023.11104] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 03/17/2023] [Indexed: 04/14/2023] Open
Abstract
Low Energy Availability (LEA) arises from the inability to cover energy needs and requirements of training or normal physiological functions. This value differs from the energy balance, which takes into account the total daily energy intake compared to all the energy expended, regardless of the amount of fat-free mass. Insufficient energy consumption affects recovery, adaptation processes, increases the risk of injury or illness, so all of this can negatively affect performance. This mini-review is written on research articles in Pubmed database related to LEA in endurance-trained men and its impact on performance and testosterone. This article also clarifies the prevalence of LEA in male endurance athletes and its correlation to Relative Energy Deficiency in Sports (RED-S). LEA occurs in male endurance athletes and correlates with decreased testosterone levels, decreased bone density and also Resting Metabolic Rate. In endurance-trained men, there is great potential for the negative consequences of low energy availability. It can also be said that there are possibilities for primary screening, so we recommend regular check-ups of blood markers, body structure and keeping not only training but also dietary records, which can increase awareness of an adequate energy balance.
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Affiliation(s)
- Martin Cupka
- Comenius University in Bratislava, Faculty of Physical Education and Sport, Department of Biological and Medical Sciences, Bratislava.
| | - Milan Sedliak
- Comenius University in Bratislava, Faculty of Physical Education and Sport, Department of Biological and Medical Sciences, Bratislava.
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Kalpana K, Cherian KS, Khanna GL. Energy availability and RED-S risk assessment among Kho-Kho players in India. SPORT SCIENCES FOR HEALTH 2022; 19:1-8. [PMID: 36061453 PMCID: PMC9425793 DOI: 10.1007/s11332-022-00996-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 07/29/2022] [Indexed: 11/26/2022]
Abstract
Purpose Energy availability (EA) is considered an important measure for athletes, particularly due to the possible health and performance outcomes defined under the RED-S. Low EA is reported to have far-reaching health consequences among female athletes, especially in weight-sensitive sport. However, it is less explored among male athletes, particularly in the traditional Indian tag sport called Kho-Kho. This cross-sectional observational study aimed to determine the prevalence of LEA and associated RED-S health and performance outcomes among Kho-Kho players. Methods Fifty-two male national-level Kho-Kho players aged 16-31 years were assessed for energy availability, bone mineral density (BMD), sleep quality, disordered eating, selected metabolic (hemoglobin, blood glucose, etc.) and performance outcomes (agility, speed, and power) as per RED-S risk assessment tool. Differences across the low EA (≤ 25 kcal/ kg fat-free mass) and Optimal EA (> 25 kcal/ kg fat-free mass) groups were evaluated using the Independent Samples t test and the chi-square test. Results Low EA among athletes was associated with lower z-scores for BMD, sleep quality and agility, compared to athletes with optimal EA. At least one moderate-to-high RED-S risk outcome was prevalent among 98% of the Kho-Kho players, irrespective of EA. Most athletes exhibited a lower EAT score and disordered eating outcomes, with no significant differences across groups. Conclusion The male Kho-Kho players showed a prevalence of low EA that can be due to higher training loads and unintentional under-eating, not related to an eating disorder. The players also exhibited higher RED-S risk outcomes; however, it was irrespective of low EA.
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Affiliation(s)
- Kommi Kalpana
- Faculty of Sports, Manav Rachna International Institute of Research and Studies, Delhi-NCR, India
| | | | - Gulshan Lal Khanna
- Faculty of Sports, Manav Rachna International Institute of Research and Studies, Delhi-NCR, India
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Relationship of Carbohydrate Intake during a Single-Stage One-Day Ultra-Trail Race with Fatigue Outcomes and Gastrointestinal Problems: A Systematic Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18115737. [PMID: 34071815 PMCID: PMC8197833 DOI: 10.3390/ijerph18115737] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 05/21/2021] [Accepted: 05/24/2021] [Indexed: 12/16/2022]
Abstract
Due to the high metabolic and physical demands in single-stage one-day ultra-trail (SOUT) races, athletes should be properly prepared in both physical and nutritional aspects in order to delay fatigue and avoid associated difficulties. However, high carbohydrate (CHO) intake would seem to increase gastrointestinal (GI) problems. The main purpose of this systematic review was to evaluate CHO intake during SOUT events as well as its relationship with fatigue (in terms of internal exercise load, exercise-induced muscle damage (EIMD) and post-exercise recovery) and GI problems. A structured search was carried out in accordance with PRISMA guidelines in the following: Web of Science, Cochrane Library and Scopus databases up to 16 March 2021. After conducting the search and applying the inclusion/exclusion criteria, eight articles in total were included in this systematic review, in all of which CHO intake involved gels, energy bars and sports drinks. Two studies associated higher CHO consumption (120 g/h) with an improvement in internal exercise load. Likewise, these studies observed that SOUT runners whose intake was 120 g/h could benefit by limiting the EIMD observed by CK (creatine kinase), LDH (lactate dehydrogenase) and GOT (aspartate aminotransferase), and also improve recovery of high intensity running capacity 24 h after a trail marathon. In six studies, athletes had GI symptoms between 65–82%. In summary, most of the runners did not meet CHO intake standard recommendations for SOUT events (90 g/h), while athletes who consumed more CHO experienced a reduction in internal exercise load, limited EIMD and improvement in post-exercise recovery. Conversely, the GI symptoms were recurrent in SOUT athletes depending on altitude, environmental conditions and running speed. Therefore, a high CHO intake during SOUT events is important to delay fatigue and avoid GI complications, and to ensure high intake, it is necessary to implement intestinal training protocols.
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Tiller NB, Roberts JD, Beasley L, Chapman S, Pinto JM, Smith L, Wiffin M, Russell M, Sparks SA, Duckworth L, O'Hara J, Sutton L, Antonio J, Willoughby DS, Tarpey MD, Smith-Ryan AE, Ormsbee MJ, Astorino TA, Kreider RB, McGinnis GR, Stout JR, Smith JW, Arent SM, Campbell BI, Bannock L. International Society of Sports Nutrition Position Stand: nutritional considerations for single-stage ultra-marathon training and racing. J Int Soc Sports Nutr 2019; 16:50. [PMID: 31699159 PMCID: PMC6839090 DOI: 10.1186/s12970-019-0312-9] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 09/24/2019] [Indexed: 12/12/2022] Open
Abstract
Background In this Position Statement, the International Society of Sports Nutrition (ISSN) provides an objective and critical review of the literature pertinent to nutritional considerations for training and racing in single-stage ultra-marathon. Recommendations for Training. i) Ultra-marathon runners should aim to meet the caloric demands of training by following an individualized and periodized strategy, comprising a varied, food-first approach; ii) Athletes should plan and implement their nutrition strategy with sufficient time to permit adaptations that enhance fat oxidative capacity; iii) The evidence overwhelmingly supports the inclusion of a moderate-to-high carbohydrate diet (i.e., ~ 60% of energy intake, 5–8 g·kg− 1·d− 1) to mitigate the negative effects of chronic, training-induced glycogen depletion; iv) Limiting carbohydrate intake before selected low-intensity sessions, and/or moderating daily carbohydrate intake, may enhance mitochondrial function and fat oxidative capacity. Nevertheless, this approach may compromise performance during high-intensity efforts; v) Protein intakes of ~ 1.6 g·kg− 1·d− 1 are necessary to maintain lean mass and support recovery from training, but amounts up to 2.5 g.kg− 1·d− 1 may be warranted during demanding training when calorie requirements are greater; Recommendations for Racing. vi) To attenuate caloric deficits, runners should aim to consume 150–400 Kcal·h− 1 (carbohydrate, 30–50 g·h− 1; protein, 5–10 g·h− 1) from a variety of calorie-dense foods. Consideration must be given to food palatability, individual tolerance, and the increased preference for savory foods in longer races; vii) Fluid volumes of 450–750 mL·h− 1 (~ 150–250 mL every 20 min) are recommended during racing. To minimize the likelihood of hyponatraemia, electrolytes (mainly sodium) may be needed in concentrations greater than that provided by most commercial products (i.e., > 575 mg·L− 1 sodium). Fluid and electrolyte requirements will be elevated when running in hot and/or humid conditions; viii) Evidence supports progressive gut-training and/or low-FODMAP diets (fermentable oligosaccharide, disaccharide, monosaccharide and polyol) to alleviate symptoms of gastrointestinal distress during racing; ix) The evidence in support of ketogenic diets and/or ketone esters to improve ultra-marathon performance is lacking, with further research warranted; x) Evidence supports the strategic use of caffeine to sustain performance in the latter stages of racing, particularly when sleep deprivation may compromise athlete safety.
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Affiliation(s)
- Nicholas B Tiller
- Division of Pulmonary and Critical Care Physiology and Medicine, The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, CA, USA. .,Academy of Sport and Physical Activity, Faculty of Health and Wellbeing, Sheffield Hallam University, Sheffield, UK.
| | - Justin D Roberts
- Cambridge Centre for Sport and Exercise Sciences, School of Psychology and Sports Science, Anglia Ruskin University, Cambridge, UK.
| | - Liam Beasley
- Cambridge Centre for Sport and Exercise Sciences, School of Psychology and Sports Science, Anglia Ruskin University, Cambridge, UK
| | - Shaun Chapman
- Cambridge Centre for Sport and Exercise Sciences, School of Psychology and Sports Science, Anglia Ruskin University, Cambridge, UK
| | - Jorge M Pinto
- Cambridge Centre for Sport and Exercise Sciences, School of Psychology and Sports Science, Anglia Ruskin University, Cambridge, UK
| | - Lee Smith
- Cambridge Centre for Sport and Exercise Sciences, School of Psychology and Sports Science, Anglia Ruskin University, Cambridge, UK
| | - Melanie Wiffin
- Cambridge Centre for Sport and Exercise Sciences, School of Psychology and Sports Science, Anglia Ruskin University, Cambridge, UK
| | - Mark Russell
- School of Social and Health Sciences, Leeds Trinity University, Leeds, UK
| | - S Andy Sparks
- Sport Nutrition and Performance Research Group, Department of Sport and Physical Activity, Edge Hill University, Ormskirk, Lancashire, UK
| | | | - John O'Hara
- Carnegie School of Sport, Leeds Beckett University, Leeds, UK
| | - Louise Sutton
- Carnegie School of Sport, Leeds Beckett University, Leeds, UK
| | - Jose Antonio
- College of Health Care Sciences, Nova Southeastern University, Fort Lauderdale, FL, USA
| | - Darryn S Willoughby
- Department of Health, Human Performance, and Recreation, Baylor University, Waco, TX, USA
| | - Michael D Tarpey
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Abbie E Smith-Ryan
- Department of Exercise and Sport Science, University of North Carolina, Chapel Hill, NC, USA
| | - Michael J Ormsbee
- Institute of Sports Sciences & Medicine, Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL, USA.,Discipline of Biokinetics, Exercise and Leisure Sciences, School of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Todd A Astorino
- Department of Kinesiology, California State University San Marcos, San Marcos, CA, USA
| | - Richard B Kreider
- Department of Health & Kinesiology, Texas A&M University, College Station, TX, USA
| | - Graham R McGinnis
- Kinesiology and Nutrition Sciences, University of Nevada, Las Vegas, NV, USA
| | - Jeffrey R Stout
- College of Health Professions and Sciences, University of Central Florida, Orlando, FL, USA
| | - JohnEric W Smith
- Department of Kinesiology, Mississippi State University, Mississippi, MS, USA
| | - Shawn M Arent
- Department of Exercise Science, University of South Carolina, Columbia, SC, USA
| | - Bill I Campbell
- Exercise Science Program, Performance & Physique Enhancement Laboratory, University of South Florida, Tampa, FL, USA
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Abstract
Ultramarathon running events and participation numbers have increased progressively over the past three decades. Besides the exertion of prolonged running with or without a loaded pack, such events are often associated with challenging topography, environmental conditions, acute transient lifestyle discomforts, and/or event-related health complications. These factors create a scenario for greater nutritional needs, while predisposing ultramarathon runners to multiple nutritional intake barriers. The current review aims to explore the physiological and nutritional demands of ultramarathon running and provide general guidance on nutritional requirements for ultramarathon training and competition, including aspects of race nutrition logistics. Research outcomes suggest that daily dietary carbohydrates (up to 12 g·kg-1·day-1) and multiple-transportable carbohydrate intake (∼90 g·hr-1 for running distances ≥3 hr) during exercise support endurance training adaptations and enhance real-time endurance performance. Whether these intake rates are tolerable during ultramarathon competition is questionable from a practical and gastrointestinal perspective. Dietary protocols, such as glycogen manipulation or low-carbohydrate high-fat diets, are currently popular among ultramarathon runners. Despite the latter dietary manipulation showing increased total fat oxidation rates during submaximal exercise, the role in enhancing ultramarathon running performance is currently not supported. Ultramarathon runners may develop varying degrees of both hypohydration and hyperhydration (with accompanying exercise-associated hyponatremia), dependent on event duration, and environmental conditions. To avoid these two extremes, euhydration can generally be maintained through "drinking to thirst." A well practiced and individualized nutrition strategy is required to optimize training and competition performance in ultramarathon running events, whether they are single stage or multistage.
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Nikolaidis PT, Veniamakis E, Rosemann T, Knechtle B. Nutrition in Ultra-Endurance: State of the Art. Nutrients 2018; 10:nu10121995. [PMID: 30558350 PMCID: PMC6315825 DOI: 10.3390/nu10121995] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 12/02/2018] [Accepted: 12/11/2018] [Indexed: 11/18/2022] Open
Abstract
Athletes competing in ultra-endurance sports should manage nutritional issues, especially with regards to energy and fluid balance. An ultra-endurance race, considered a duration of at least 6 h, might induce the energy balance (i.e., energy deficit) in levels that could reach up to ~7000 kcal per day. Such a negative energy balance is a major health and performance concern as it leads to a decrease of both fat and skeletal muscle mass in events such as 24-h swimming, 6-day cycling or 17-day running. Sport anemia caused by heavy exercise and gastrointestinal discomfort, under hot or cold environmental conditions also needs to be considered as a major factor for health and performance in ultra-endurance sports. In addition, fluid losses from sweat can reach up to 2 L/h due to increased metabolic work during prolonged exercise and exercise under hot environments that might result in hypohydration. Athletes are at an increased risk for exercise-associated hyponatremia (EAH) and limb swelling when intake of fluids is greater than the volume lost. Optimal pre-race nutritional strategies should aim to increase fat utilization during exercise, and the consumption of fat-rich foods may be considered during the race, as well as carbohydrates, electrolytes, and fluid. Moreover, to reduce the risk of EAH, fluid intake should include sodium in the amounts of 10–25 mmol to reduce the risk of EAH and should be limited to 300–600 mL per hour of the race.
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Affiliation(s)
- Pantelis T Nikolaidis
- Laboratory of Exercise Testing, Hellenic Air Force Academy, 13671 Dekelia, Greece.
- Exercise Physiology Laboratory, 18450 Nikaia, Greece.
| | - Eleftherios Veniamakis
- Department of Nutrition and Dietetics, Technological Educational Institute, 72300 Sitia, Greece.
| | - Thomas Rosemann
- Institute of General Practice and for Health Services Research, University of Zurich, 8091 Zurich, Switzerland.
| | - Beat Knechtle
- Institute of General Practice and for Health Services Research, University of Zurich, 8091 Zurich, Switzerland.
- Medbase St. Gallen Am Vadianplatz, 9001 St. Gallen, Switzerland.
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Knechtle B, Nikolaidis PT. Physiology and Pathophysiology in Ultra-Marathon Running. Front Physiol 2018; 9:634. [PMID: 29910741 PMCID: PMC5992463 DOI: 10.3389/fphys.2018.00634] [Citation(s) in RCA: 152] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 05/11/2018] [Indexed: 12/31/2022] Open
Abstract
In this overview, we summarize the findings of the literature with regards to physiology and pathophysiology of ultra-marathon running. The number of ultra-marathon races and the number of official finishers considerably increased in the last decades especially due to the increased number of female and age-group runners. A typical ultra-marathoner is male, married, well-educated, and ~45 years old. Female ultra-marathoners account for ~20% of the total number of finishers. Ultra-marathoners are older and have a larger weekly training volume, but run more slowly during training compared to marathoners. Previous experience (e.g., number of finishes in ultra-marathon races and personal best marathon time) is the most important predictor variable for a successful ultra-marathon performance followed by specific anthropometric (e.g., low body mass index, BMI, and low body fat) and training (e.g., high volume and running speed during training) characteristics. Women are slower than men, but the sex difference in performance decreased in recent years to ~10–20% depending upon the length of the ultra-marathon. The fastest ultra-marathon race times are generally achieved at the age of 35–45 years or older for both women and men, and the age of peak performance increases with increasing race distance or duration. An ultra-marathon leads to an energy deficit resulting in a reduction of both body fat and skeletal muscle mass. An ultra-marathon in combination with other risk factors, such as extreme weather conditions (either heat or cold) or the country where the race is held, can lead to exercise-associated hyponatremia. An ultra-marathon can also lead to changes in biomarkers indicating a pathological process in specific organs or organ systems such as skeletal muscles, heart, liver, kidney, immune and endocrine system. These changes are usually temporary, depending on intensity and duration of the performance, and usually normalize after the race. In longer ultra-marathons, ~50–60% of the participants experience musculoskeletal problems. The most common injuries in ultra-marathoners involve the lower limb, such as the ankle and the knee. An ultra-marathon can lead to an increase in creatine-kinase to values of 100,000–200,000 U/l depending upon the fitness level of the athlete and the length of the race. Furthermore, an ultra-marathon can lead to changes in the heart as shown by changes in cardiac biomarkers, electro- and echocardiography. Ultra-marathoners often suffer from digestive problems and gastrointestinal bleeding after an ultra-marathon is not uncommon. Liver enzymes can also considerably increase during an ultra-marathon. An ultra-marathon often leads to a temporary reduction in renal function. Ultra-marathoners often suffer from upper respiratory infections after an ultra-marathon. Considering the increased number of participants in ultra-marathons, the findings of the present review would have practical applications for a large number of sports scientists and sports medicine practitioners working in this field.
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Affiliation(s)
- Beat Knechtle
- Institute of Primary Care, University of Zurich, Zurich, Switzerland
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Williamson E. Nutritional implications for ultra-endurance walking and running events. EXTREME PHYSIOLOGY & MEDICINE 2016; 5:13. [PMID: 27895900 PMCID: PMC5117571 DOI: 10.1186/s13728-016-0054-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/04/2016] [Accepted: 11/01/2016] [Indexed: 01/15/2023]
Abstract
This paper examines the various nutritional challenges which athletes encounter in preparing for and participating in ultra-endurance walking and running events. Special attention is paid to energy level, performance, and recovery within the context of athletes' intake of carbohydrate, protein, fat, and various vitamins and minerals. It outlines, by way of a review of literature, those factors which promote optimal performance for the ultra-endurance athlete and provides recommendations from multiple researchers concerned with the nutrition and performance of ultra-endurance athletes. Despite the availability of some research about the subject, there is a paucity of longitudinal material which examines athletes by nature and type of ultra-endurance event, gender, age, race, and unique physiological characteristics. Optimal nutrition results in a decreased risk of energy depletion, better performance, and quicker full-recovery.
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Affiliation(s)
- Eric Williamson
- Department of Exercise Science, University of Toronto, 55 Harbord Street, Toronto, ON M5S 2W6 Canada
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Halsey LG, Stroud MA. 100 Years Since Scott Reached the Pole: A Century of Learning About the Physiological Demands of Antarctica. Physiol Rev 2012; 92:521-36. [DOI: 10.1152/physrev.00031.2011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The 1910–1913 Terra Nova Expedition to the Antarctic, led by Captain Robert Falcon Scott, was a venture of science and discovery. It is also a well-known story of heroism and tragedy since his quest to reach the South Pole and conduct research en route, while successful was also fateful. Although Scott and his four companions hauled their sledges to the Pole, they died on their return journey either directly or indirectly from the extreme physiological stresses they experienced. One hundred years on, our understanding of such stresses caused by Antarctic extremes and how the body reacts to severe exercise, malnutrition, hypothermia, high altitude, and sleep deprivation has greatly advanced. On the centenary of Scott's expedition to the bottom of the Earth, there is still controversy surrounding whether the deaths of those five men could have, or should have, been avoided. This paper reviews present-day knowledge related to the physiology of sustained man-hauling in Antarctica and contrasts this with the comparative ignorance about these issues around the turn of the 20th century. It closes by considering whether, with modern understanding about the effects of such a scenario on the human condition, Scott could have prepared and managed his team differently and so survived the epic 1,600-mile journey. The conclusion is that by carrying rations with a different composition of macromolecules, enabling greater calorific intake at similar overall weight, Scott might have secured the lives of some of the party, and it is also possible that enhanced levels of vitamin C in his rations, albeit difficult to achieve in 1911, could have significantly improved their survival chances. Nevertheless, even with today's knowledge, a repeat attempt at his expedition would by no means be bound to succeed.
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Affiliation(s)
- Lewis G. Halsey
- University of Roehampton, London, and National Institute for Health Research Biomedical Research Unit in Nutrition, Southampton University Hospitals Trust, Southampton, United Kingdom
| | - Mike A. Stroud
- University of Roehampton, London, and National Institute for Health Research Biomedical Research Unit in Nutrition, Southampton University Hospitals Trust, Southampton, United Kingdom
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Abstract
Dinghy sailing is a physically challenging sport with competitors on water for several hours. Regulations and space in the boat limit the amount of food and fluid competitors can carry. Consequently, it is possible that the hydration and nutritional status of dinghy sailors may be compromised while racing. Despite this, the food and fluid intake of sailors while racing are unknown. The aim of this study was to assess the dietary intake of a group of club sailors while racing and compare this with current sports nutrition guidelines. Thirty-five sailors (9 females, 26 males) were monitored during a club regatta. Body mass changes were measured before and after racing, as were food and fluid intake. Results showed that most participants were in negative fluid balance after racing (males: mean -2.1%[95% confidence limits -1.7 to -2.5%]; females: -0.9%[0 to -1.8%]), most likely due to low voluntary fluid intake (males: 1215 ml [734 to 1695 ml]; females: 792 ml [468 to 1117 m]). Carbohydrate intake (males: 59 g [21 to 97 g]; females: 30 g [0 to 61 g]) was below recommendations for normal sports activity. Results revealed that the nutritional practices of club sailors do not comply with current sports nutrition guidelines. However, the performance implications of a compromise in nutrient intake remain to be investigated. Practical advice on methods of overcoming space limitations for the carriage of adequate fluid and food is offered.
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Affiliation(s)
- Gary Slater
- High Performance Group, Singapore Sports Council, Singapore.
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12
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Luks AM, Robertson HT, Swenson ER. An ultracyclist with pulmonary edema during the Bicycle Race Across America. Med Sci Sports Exerc 2007; 39:8-12. [PMID: 17218877 DOI: 10.1249/01.mss.0000235885.79110.79] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ultraendurance athletic events tax the limits of physiological homeostasis. Maintenance of sodium and water balance is a particularly difficult challenge in such events. We present the case of a 38-yr-old participant in the Bicycle Race Across America who developed severe pulmonary edema while cycling at an altitude of 2380 m on the fourth day of the race. With hospitalization and standard support for pulmonary edema, he made a quick, full recovery. A post-race work-up revealed no evidence of underlying cardiopulmonary disease or susceptibility to high-altitude pulmonary edema. His weight on the day of hospitalization was 2.7 kg greater than his pre-race weight. We hypothesize that his excessive daily sodium intake (23-25 g, or 1000-1100 mEq) during the course of the race likely led to an expanded extracellular volume, increased hydrostatic pressure, and decreased oncotic pressure. These factors, in combination with ambient hypoxia, elevated cardiac output, and reduced renal perfusion expected with sustained, high-level exercise, may have led to the development of acute pulmonary edema. This case highlights the pitfalls of overly aggressive sodium intake in endurance races, particularly when such races are conducted at high altitude, where the hypoxia-induced rise in pulmonary artery pressures may amplify the effects of changes in hydrostatic and oncotic pressure that occur with extracellular volume expansion.
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Affiliation(s)
- Andrew M Luks
- Division of Pulmonary and Critical Care Medicine, University of Washington, Seattle, WA 98108, USA.
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Watelet J, Bigard MA. [Gastrointestinal and liver disorders in athletes]. GASTROENTEROLOGIE CLINIQUE ET BIOLOGIQUE 2005; 29:522-32. [PMID: 15980745 DOI: 10.1016/s0399-8320(05)82123-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
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Ainslie PN, Campbell IT, Lambert JP, MacLaren DPM, Reilly T. Physiological and Metabolic Aspects of Very Prolonged Exercise with Particular Reference to Hill Walking. Sports Med 2005; 35:619-47. [PMID: 16026174 DOI: 10.2165/00007256-200535070-00006] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Hill walking is a popular recreational activity in the developed world, yet it has the potential to impose severe stress simultaneously upon several regulatory systems. Information regarding the physiological strain imposed by prolonged walking outdoors in adverse climatic conditions was reported almost four decades ago and recent research has extended some of this work. These data indicate that once the walker fatigues and starts to slow or stops walking altogether, the rate of heat production falls dramatically. This decrease alone predisposes to the development of hypothermia. These processes, in adverse weather conditions and/or during periods when the level of exertion is low (with low heat production), will be accelerated. Since the majority of walkers pursue this activity in groups, the less fit walkers may be more susceptible to fatigue when exercising at a higher relative intensity compared with their fitter counterparts. The best physiological offset for hypothermia is to maintain heat production by means of exercise, and so fatigue becomes a critical predisposing factor; it is as important to facilitate heat loss, especially during periods of high exertion, as it is to maintain heat production and preserve insulation. This can be partly achieved by clothing adjustments and consideration of the intensity of exercise. Failure to provide adequate energy intake during hill walking activities has been associated with decreased performance (particularly with respect to balance) and impaired thermoregulation. Such impairments may increase susceptibly to both fatigue and injury whilst pursuing this form of activity outdoors. The prolonged low to moderate intensity of activity experienced during a typical hill walk elicits marked changes in the metabolic and hormonal milieu. Available data suggest that during hill walking, even during periods of acute negative energy balance, blood glucose concentrations are maintained. The maintenance of blood glucose concentrations seems to reflect the presence of an alternative fuel source, a hormonally induced increase in fat mobilisation. Such enhancement of fat mobilisation should make it easier to maintain blood glucose by decreasing carbohydrate oxidation and promoting gluconeogenesis, thus sparing glucose utilisation by active muscle. During strenuous hill walking, older age walkers may be particularly prone to dehydration and decreased physical and mental performance, when compared with their younger counterparts. In summary, high rates of energy expenditure and hypohydration are likely to be closely linked to the activity. Periods of adverse weather, low energy intake, lowered fitness or increased age, can all increase the participants' susceptibility to injury, fatigue and hypothermia in the mountainous environment.
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Affiliation(s)
- Philip N Ainslie
- Department of Physiology and Biophysics, University of Calgary, Faculty of Medicine, Calgary, Canada.
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15
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Burke LM. Energy needs of athletes. CANADIAN JOURNAL OF APPLIED PHYSIOLOGY = REVUE CANADIENNE DE PHYSIOLOGIE APPLIQUEE 2002; 26 Suppl:S202-19. [PMID: 11897896 DOI: 10.1139/h2001-055] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Each athlete has unique energy requirements, which underpin their ability to meet total nutritional goals. For everyday dietary planning and evaluation, energy requirements can be predicted via estimations of RMR and activity levels. Research methods such as indirect calorimetry and DLW allow energy requirements to be measured, and may be useful to confirm situations in which an athlete has a true energy balance anomaly. There is some evidence that individual athletes may have reduced energy requirements, although this occurs less frequently than is reported. Most self-reports of food intake substantially under-estimate energy intake, due to under-reporting or under-eating during the period of record keeping. Many athletes are over-focused on reducing body mass and body fat below levels that are consistent with long-term health and performance. Restrained eating can cause significant detrimental outcomes to body function. Leptin may be involved in modulating or mediating some of these changes. Athletes should use their energy budget to choose foods that provide macronutrient and micronutrient needs for optimal health and performance. Practical advice may help athletes to achieve energy intake challenges.
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Affiliation(s)
- L M Burke
- Department of Sports Nutrition, Australian Institute of Sport, Belconnen, Australia
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Abstract
It is well known that fluid and electrolyte balance are critical to optimal exercise performance and, moreover, health maintenance. Most research conducted on extreme sporting endeavour (>3 hours) is based on case studies and studies involving small numbers of individuals. Ultra-endurance sportsmen and women typically do not meet their fluid needs during exercise. However, successful athletes exercising over several consecutive days come close to meeting fluid needs. It is important to try to account for all factors influencing bodyweight changes, in addition to fluid loss, and all sources of water input. Increasing ambient temperature and humidity can increase the rate of sweating by up to approximately 1 L/h. Depending on individual variation, exercise type and particularly intensity, sweat rates can vary from extremely low values to more than 3 L/h. Over-hydration, although not frequently observed, can also present problems, as can inappropriate fluid composition. Over-hydrating or meeting fluid needs during very long-lasting exercise in the heat with low or negligible sodium intake can result in reduced performance and, not infrequently, hyponatraemia. Thus, with large rates of fluid ingestion, even measured just to meet fluid needs, sodium intake is vital and an increased beverage concentration [30 to 50 mmol/L (1.7 to 2.9 g NaCl/L) may be beneficial. If insufficient fluids are taken during exercise, sodium is necessary in the recovery period to reduce the urinary output and increase the rate of restoration of fluid balance. Carbohydrate inclusion in a beverage can affect the net rate of water assimilation and is also important to supplement endogenous reserves as a substrate for exercising muscles during ultra-endurance activity. To enhance water absorption, glucose and/or glucose-containing carbohydrates (e.g. sucrose, maltose) at concentrations of 3 to 5% weight/volume are recommended. Carbohydrate concentrations above this may be advantageous in terms of glucose oxidation and maintaining exercise intensity, but will be of no added advantage and, if hyperosmotic, will actually reduce the net rate of water absorption. The rate of fluid loss may exceed the capacity of the gastrointestinal tract to assimilate fluids. Gastric emptying, in particular, may be below the rate of fluid loss, and therefore, individual tolerance may dictate the maximum rate of fluid intake. There is large individual variation in gastric emptying rate and tolerance to larger volumes. Training to drink during exercise is recommended and may enhance tolerance.
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Affiliation(s)
- N J Rehrer
- School of Physical Education and Department of Human Nutrition, Otago University, Dunedin, New Zealand.
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Burke LM, Cox GR, Culmmings NK, Desbrow B. Guidelines for daily carbohydrate intake: do athletes achieve them? Sports Med 2001; 31:267-99. [PMID: 11310548 DOI: 10.2165/00007256-200131040-00003] [Citation(s) in RCA: 162] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Official dietary guidelines for athletes are unanimous in their recommendation of high carbohydrate (CHO) intakes in routine or training diets. These guidelines have been criticised on the basis of a lack of scientific support for superior training adaptations and performance, and the apparent failure of successful athletes to achieve such dietary practices. Part of the problem rests with the expression of CHO intake guidelines in terms of percentage of dietary energy. It is preferable to provide recommendations for routine CHO intake in grams (relative to the body mass of the athlete) and allow flexibility for the athlete to meet these targets within the context of their energy needs and other dietary goals. CHO intake ranges of 5 to 7 g/kg/day for general training needs and 7 to 10 g/kg/day for the increased needs of endurance athletes are suggested. The limitations of dietary survey techniques should be recognised when assessing the adequacy of the dietary practices of athletes. In particular, the errors caused by under-reporting or undereating during the period of the dietary survey must be taken into account. A review of the current dietary survey literature of athletes shows that a typical male athlete achieves CHO intake within the recommended range (on a g/kg basis). Individual athletes may need nutritional education or dietary counselling to fine-tune their eating habits to meet specific CHO intake targets. Female athletes, particularly endurance athletes, are less likely to achieve these CHO intake guidelines. This is due to chronic or periodic restriction of total energy intake in order to achieve or maintain low levels of body fat. With professional counselling, female athletes may be helped to find a balance between bodyweight control issues and fuel intake goals. Although we look to the top athletes as role models, it is understandable that many do not achieve optimal nutrition practices. The real or apparent failure of these athletes to achieve the daily CHO intakes recommended by sports nutritionists does not necessarily invalidate the benefits of meeting such guidelines. Further longitudinal studies of training adaptation and performance are needed to determine differences in the outcomes of high versus moderate CHO intakes. In the meantime, the recommendations of sports nutritionists are based on plentiful evidence that increased CHO availability enhances endurance and performance during single exercise sessions.
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Affiliation(s)
- L M Burke
- Department of Sports Nutrition, Australian Institute of Sport, Belconnen, ACT, Australia.
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Ferreira AMD, Ribeiro BG, Soares EDA. Consumo de carboidratos e lipídios no desempenho em exercícios de ultra-resistência. REV BRAS MED ESPORTE 2001. [DOI: 10.1590/s1517-86922001000200005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A nutrição é uma importante ferramenta dentro da prática desportiva. Dentre as modalidades esportivas, a nutrição exerce uma grande influência nos chamados "esportes de desafio", que são as provas de ultra-resistência ou de longa duração. O custo energético de uma prova de ultra-resistência pode variar de 5.000 a 18.000kcal por dia. É amplamente aceito que o consumo de carboidratos antes e durante exercícios prolongados irá retardar o aparecimento da fadiga, poupando o glicogênio hepático e muscular e fornecendo glicose diretamente para os músculos em atividade. Recomenda-se que a dieta de atletas de ultra-resistência possua 70% ou mais, ou de 7 a 10 gramas por quilo de peso corporal de carboidratos. Porém, apesar da melhora apresentada com a nutrição bem planejada, alguns pesquisadores procuram desenvolver novas intervenções nutricionais, visando a melhora do rendimento, que continuam a ser estudadas, como a suplementação com lipídios, através do consumo de triglicerídeos de cadeia média (TCM) ou de dietas ricas em lipídios nos dias que antecedem a competição. Sendo assim, esta revisão possui como objetivo elucidar como os carboidratos e os lipídios podem influenciar o desempenho nos exercícios de ultra-resistência.
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Kleiner SM. Water: an essential but overlooked nutrient. JOURNAL OF THE AMERICAN DIETETIC ASSOCIATION 1999; 99:200-6. [PMID: 9972188 DOI: 10.1016/s0002-8223(99)00048-6] [Citation(s) in RCA: 159] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Water is an essential nutrient required for life. To be well hydrated, the average sedentary adult man must consume at least 2,900 mL (12 c) fluid per day, and the average sedentary adult woman at least 2,200 mL (9 c) fluid per day, in the form of noncaffeinated, nonalcoholic beverages, soups, and foods. Solid foods contribute approximately 1,000 mL (4 c) water, with an additional 250 mL (1 c) coming from the water of oxidation. The Nationwide Food Consumption Surveys indicate that a portion of the population may be chronically mildly dehydrated. Several factors may increase the likelihood of chronic, mild dehydration, including a poor thirst mechanism, dissatisfaction with the taste of water, common consumption of the natural diuretics caffeine and alcohol, participation in exercise, and environmental conditions. Dehydration of as little as 2% loss of body weight results in impaired physiological and performance responses. New research indicates that fluid consumption in general and water consumption in particular can have an effect on the risk of urinary stone disease; cancers of the breast, colon, and urinary tract; childhood and adolescent obesity; mitral valve prolapse; salivary gland function; and overall health in the elderly. Dietitians should be encouraged to promote and monitor fluid and water intake among all of their clients and patients through education and to help them design a fluid intake plan. The influence of chronic mild dehydration on health and disease merits further research.
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Affiliation(s)
- S M Kleiner
- Nutritional Sciences Program, University of Washington, Seattle, USA
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Affiliation(s)
- M Stroud
- Institute of Human Nutrition, Southampton General Hospital, UK
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