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Johnson KB, Connolly CP, Cho SP, Miller TK, Sallis RE, Hiller WDB. Clinical presentation of exercise-associated hyponatremia in male and female IRONMAN® triathletes over three decades. Scand J Med Sci Sports 2023; 33:1841-1849. [PMID: 37204065 DOI: 10.1111/sms.14401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 04/16/2023] [Accepted: 05/09/2023] [Indexed: 05/20/2023]
Abstract
PURPOSE Exercise-associated hyponatremia (EAH) is common in ultra-endurance events and severe cases are more common in females. The purpose of this paper is to compare the clinical presentation of EAH between male and female triathletes in ultra-endurance competitions. METHODS Medical records with sodium concentrations (n = 3138) from the IRONMAN® World Championships over the timeframe of 1989-2019 were reviewed for both male (n = 2253) and female (n = 885) competitors. Logistic regression was used to explore the relationships between sex, sodium concentration, and various clinical presentations. RESULTS When comparing male and female triathletes, clinical variables found to have a different relationship with sodium concentration include altered mental status (inversely related in males and not related in females), abdominal pain, muscle cramps, hypotension, and tachycardia (directly related in males and not related in females), and vomiting and hypokalemia (not related in males and inversely related in females). Overall, males lost significantly more weight than females, and notably, approximately half of all athletes were dehydrated and lost weight. CONCLUSIONS Altered mental status, vomiting, abdominal pain, muscle cramps, hypotension, tachycardia, and hyperkalemia appear to present differently between sexes when comparing hyponatremic to eunatremic athletes. Although overhydration is the most common etiology of hypervolemic hyponatremia, hypovolemic hyponatremia comprises a significant amount of hyponatremic triathletes. Further understanding of how EAH presents helps athletes and medical professionals identify it early and prevent life-threatening complications.
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Affiliation(s)
- Kasey B Johnson
- Elson S. Floyd College of Medicine, Washington State University, Spokane, WA, USA
| | | | - Stephanie P Cho
- College of Education, Washington State University, Pullman, WA, USA
| | - Thomas K Miller
- Virginia Tech Carilion School of Medicine, Roanoke, Virginia, USA
| | - Robert E Sallis
- UC Riverside School of Medicine, Riverside, California, USA
- Kaiser Permanente, Sports Medicine, Fontana, California, USA
| | - W Douglas B Hiller
- Elson S. Floyd College of Medicine, Washington State University, Spokane, WA, USA
- John A. Burns College of Medicine at University of Hawai'i, Honolulu, Hawaii, USA
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2
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Ffrench R, Smith MD, Henderson E. Case of transient global amnesia-like syndrome after recreational cold-water swimming. BMJ Case Rep 2023; 16:e253125. [PMID: 37369527 PMCID: PMC10410986 DOI: 10.1136/bcr-2022-253125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/19/2023] [Indexed: 06/29/2023] Open
Abstract
We document a case of a transient global amnesia (TGA)-like syndrome following open water swimming. This case was atypical for TGA, in that symptoms were prolonged and ischaemic infarct was considered within the differential. MRI did not demonstrate any changes associated with acute ischaemia although did show a mild degree of small vessel change. With amnesia taking greater than 24 hours to resolve, we have labelled this case to be a TGA-like syndrome, provoked by the commonly reported TGA precipitant of cold water immersion. The possibility of a tiny, strategic infarct causing these symptoms was considered and antiplatelet therapy commenced.
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Affiliation(s)
- Ruby Ffrench
- Older people's unit, Royal United Hospitals NHS Foundation Trust, Bath, UK
| | - Matthew D Smith
- Older people's unit, Royal United Hospitals NHS Foundation Trust, Bath, UK
- Population Health Sciences, University of Bristol, Bristol, UK
| | - Emily Henderson
- Older people's unit, Royal United Hospitals NHS Foundation Trust, Bath, UK
- Population Health Sciences, University of Bristol, Bristol, UK
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Exercise-Associated Hyponatremia in Marathon Runners. J Clin Med 2022; 11:jcm11226775. [PMID: 36431252 PMCID: PMC9699060 DOI: 10.3390/jcm11226775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Revised: 11/01/2022] [Accepted: 11/05/2022] [Indexed: 11/19/2022] Open
Abstract
Exercise-associated hyponatremia (EAH) was first described as water intoxication by Noakes et al. in 1985 and has become an important topic linked to several pathological conditions. However, despite progressive research, neurological disorders and even deaths due to hyponatremic encephalopathy continue to occur. Therefore, and due to the growing popularity of exercise-associated hyponatremia, this topic is of great importance for marathon runners and all professionals involved in runners' training (e.g., coaches, medical staff, nutritionists, and trainers). The present narrative review sought to evaluate the prevalence of EAH among marathon runners and to identify associated etiological and risk factors. Furthermore, the aim was to derive preventive and therapeutic action plans for marathon runners based on current evidence. The search was conducted on PubMed, Scopus and Google Scholar using a predefined search algorithm by aggregating multiple terms (marathon run; exercise; sport; EAH; electrolyte disorder; fluid balance; dehydration; sodium concentration; hyponatremia). By this criterion, 135 articles were considered for the present study. Our results revealed that a complex interaction of different factors could cause EAH, which can be differentiated into event-related (high temperatures) and person-related (female sex) risk factors. There is variation in the reported prevalence of EAH, and two major studies indicated an incidence ranging from 7 to 15% for symptomatic and asymptomatic EAH. Athletes and coaches must be aware of EAH and its related problems and take appropriate measures for both training and competition. Coaches need to educate their athletes about the early symptoms of EAH to intervene at the earliest possible stage. In addition, individual hydration strategies need to be developed for the daily training routine, ideally in regard to sweat rate and salt losses via sweat. Future studies need to investigate the correlation between the risk factors of EAH and specific subgroups of marathon runners.
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Knechtle B, Chlíbková D, Papadopoulou S, Mantzorou M, Rosemann T, Nikolaidis PT. Exercise-Associated Hyponatremia in Endurance and Ultra-Endurance Performance-Aspects of Sex, Race Location, Ambient Temperature, Sports Discipline, and Length of Performance: A Narrative Review. ACTA ACUST UNITED AC 2019; 55:medicina55090537. [PMID: 31455034 PMCID: PMC6780610 DOI: 10.3390/medicina55090537] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Revised: 08/15/2019] [Accepted: 08/21/2019] [Indexed: 12/05/2022]
Abstract
Exercise-associated hyponatremia (EAH) is defined as a plasma sodium concentration of <135 mmol/L during or after endurance and ultra-endurance performance and was first described by Timothy Noakes when observed in ultra-marathoners competing in the Comrades Marathon in South Africa in the mid-1980s. It is well-established that a decrease in plasma sodium concentration <135 mmol/L occurs with excessive fluid intake. Clinically, a mild hyponatremia will lead to no or very unspecific symptoms. A pronounced hyponatremia (<120 mmol/L) will lead to central nervous symptoms due to cerebral edema, and respiratory failure can lead to death when plasma sodium concentration reaches values of <110–115 mmol/L. The objective of this narrative review is to present new findings about the aspects of sex, race location, sports discipline, and length of performance. The prevalence of EAH depends on the duration of an endurance performance (i.e., low in marathon running, high to very high in ultra-marathon running), the sports discipline (i.e., rather rare in cycling, more frequent in running and triathlon, and very frequent in swimming), sex (i.e., increased in women with several reported deaths), the ambient temperature (i.e., very high in hot temperatures) and the country where competition takes place (i.e., very common in the USA, very little in Europe, practically never in Africa, Asia, and Oceania). A possible explanation for the increased prevalence of EAH in women could be the so-called Varon–Ayus syndrome with severe hyponatremia, lung and cerebral edema, which was first observed in marathon runners. Regarding the race location, races in Europe seemed to be held under rather moderate conditions whereas races held in the USA were often performed under thermally stressing conditions (i.e., greater heat or greater cold).
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Affiliation(s)
- Beat Knechtle
- Medbase St. Gallen Am Vadianplatz, 9001 St. Gallen, Switzerland.
- Institute of Primary Care, University of Zurich, 8091 Zurich, Switzerland.
| | - Daniela Chlíbková
- Centre of Sports Activities, Brno University of Technology, 61669 Brno, Czech Republic
| | - Sousana Papadopoulou
- Department of Nutritional Sciences and Dietetics, International Hellenic University, 57001 Thessaloniki, Greece
| | - Maria Mantzorou
- Food Science and Nutrition Department, University of the Aegean, 81400 Myrina, Greece
| | - Thomas Rosemann
- Institute of Primary Care, University of Zurich, 8091 Zurich, Switzerland
| | - Pantelis T Nikolaidis
- Exercise Physiology Laboratory, 18450 Nikaia, Greece
- School of Health and Caring Sciences, University of West Attica, 12243 Athens, Greece
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Knechtle B, Chlíbková D, Nikolaidis PT. [Exercise-Associated Hyponatremia in Endurance Performance]. PRAXIS 2019; 108:615-632. [PMID: 31288661 DOI: 10.1024/1661-8157/a003261] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Exercise-Associated Hyponatremia in Endurance Performance Abstract. Exercise-associated hyponatremia is defined as a plasma sodium concentration of <135 mmol/l and was first described by Timothy Noakes at the Comrades Marathon in South Africa in the mid-1980s. A decrease in plasma sodium <135 mmol/l occurs with excessive fluid intake. Risk factors include long to very long endurance performance, extreme climatic conditions, female gender and competitions in the USA. Regarding its prevalence by sport, exercise-associated hyponatraemia tends to occur while swimming and running, but rarely when cycling. While mild exercise-associated hyponatremia does not lead to clinical symptoms, severe hyponatremia due to cerebral edema can lead to neurological deficits and even death. The best prevention of exercise-associated hyponatremia is the reduction of fluid intake during exercise.
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Affiliation(s)
- Beat Knechtle
- 1 Medbase St. Gallen Am Vadianplatz, St. Gallen
- 2 Institut für Hausarztmedizin, Universität Zürich, Zürich
| | - Daniela Chlíbková
- 3 Centre of Sports Activities, Brno University of Technology, Brno, Tschechien
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Simulescu V, Ilia G, Macarie L, Merghes P. Sport and energy drinks consumption before, during and after training. Sci Sports 2019. [DOI: 10.1016/j.scispo.2018.10.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Chlíbková D, Nikolaidis PT, Rosemann T, Knechtle B, Bednář J. Maintained Hydration Status After a 24-h Winter Mountain Running Race Under Extremely Cold Conditions. Front Physiol 2019; 9:1959. [PMID: 30687135 PMCID: PMC6336898 DOI: 10.3389/fphys.2018.01959] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 12/28/2018] [Indexed: 12/21/2022] Open
Abstract
Background: To date, no study has examined the hydration status of runners competing in a 24-h winter race under extremely cold environmental conditions. Therefore, the aim was to examine the effect of a 24-h race under an average temperature of -14.3°C on hydration status. Methods: Blood and urine parameters and body mass (BM) were assessed in 20 finishers (women, n = 6; men, n = 14) pre- and post-race. Results: Five (25%) ultra-runners had lower pre-race plasma sodium [Na+] and 11 (52%) had higher pre-race plasma potassium [K+] values than the reference ranges. Post-race plasma [Na+], plasma osmolality, urine osmolality and urine specific gravity remained stable (p > 0.05). The estimated fluid intake did not differ (p > 0.05) between women (0.30 ± 0.06 L/h) and men (0.46 ± 0.21 L/h). Runners with a higher number of completed ultra-marathons (r = -0.50, p = 0.024) and higher number of training kilometers (r = -0.68, p = 0.001) drank less than those with lower running experience. Pre-race and post-race plasma [Na+] were related to plasma osmolality (r = 0.65, p = 0.002, r = 0.69, p < 0.001, respectively) post-race, but not to fluid intake (p > 0.05). BM significantly decreased post-race (p = 0.002) and was not related to plasma [Na+] or fluid intake (p > 0.05). Post-race hematocrit and plasma [K+] decreased (p < 0.001) and transtubular potassium gradient increased (p = 0.008). Higher pre-race plasma [K+] was related to higher plasma [K+] loss post-race (p = -0.85, p < 0.001). Conclusion: Hydration status remained stable despite the extremely cold winter weather conditions. Overall fluid intake was probably sufficient to replenish the hydration needs of 24-h runners. Current recommendations may be too high for athletes competing in extremely cold conditions.
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Affiliation(s)
- Daniela Chlíbková
- Centre of Sports Activities, Brno University of Technology, Brno, Czechia
| | | | | | - Beat Knechtle
- Exercise Physiology Laboratory, Nikaia, Greece.,Medbase St. Gallen Am Vadianplatz, St. Gallen, Switzerland
| | - Josef Bednář
- Faculty of Mechanical Engineering, Brno University of Technology, Brno, Czechia
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Reeder JT, Choi J, Xue Y, Gutruf P, Hanson J, Liu M, Ray T, Bandodkar AJ, Avila R, Xia W, Krishnan S, Xu S, Barnes K, Pahnke M, Ghaffari R, Huang Y, Rogers JA. Waterproof, electronics-enabled, epidermal microfluidic devices for sweat collection, biomarker analysis, and thermography in aquatic settings. SCIENCE ADVANCES 2019; 5:eaau6356. [PMID: 30746456 PMCID: PMC6357724 DOI: 10.1126/sciadv.aau6356] [Citation(s) in RCA: 133] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Accepted: 12/10/2018] [Indexed: 05/18/2023]
Abstract
Noninvasive, in situ biochemical monitoring of physiological status, via the use of sweat, could enable new forms of health care diagnostics and personalized hydration strategies. Recent advances in sweat collection and sensing technologies offer powerful capabilities, but they are not effective for use in extreme situations such as aquatic or arid environments, because of unique challenges in eliminating interference/contamination from surrounding water, maintaining robust adhesion in the presence of viscous drag forces and/or vigorous motion, and preventing evaporation of collected sweat. This paper introduces materials and designs for waterproof, epidermal, microfluidic and electronic systems that adhere to the skin to enable capture, storage, and analysis of sweat, even while fully underwater. Field trials demonstrate the ability of these devices to collect quantitative in situ measurements of local sweat chloride concentration, local sweat loss (and sweat rate), and skin temperature during vigorous physical activity in controlled, indoor conditions and in open-ocean swimming.
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Affiliation(s)
- Jonathan T. Reeder
- Department of Materials Science and Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
- Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL 60208, USA
| | - Jungil Choi
- Department of Materials Science and Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
- Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL 60208, USA
| | - Yeguang Xue
- Department of Civil and Environmental Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
- Department of Mechanical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Philipp Gutruf
- Department of Materials Science and Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
- Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL 60208, USA
| | - Justin Hanson
- Department of Biological Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611 USA
| | - Mark Liu
- Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Tyler Ray
- Department of Materials Science and Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
- Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL 60208, USA
| | - Amay J. Bandodkar
- Department of Materials Science and Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
- Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL 60208, USA
| | - Raudel Avila
- Department of Civil and Environmental Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
- Department of Mechanical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Wei Xia
- Department of Civil and Environmental Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
- State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi’an Jiaotong University, Xi’an, Shaanxi 710049, China
| | - Siddharth Krishnan
- Department of Materials Science and Engineering and Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Shuai Xu
- Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL 60208, USA
- Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago IL 60611 USA
| | - Kelly Barnes
- Gatorade Sports Science Institute, 617 W. Main St., Barrington, IL 60010, USA
| | - Matthew Pahnke
- Gatorade Sports Science Institute, 617 W. Main St., Barrington, IL 60010, USA
| | - Roozbeh Ghaffari
- Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL 60208, USA
- Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
- Epicore Biosystems Inc., Cambridge, MA 02139, USA
| | - Yonggang Huang
- Department of Materials Science and Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
- Department of Civil and Environmental Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
- Department of Mechanical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
| | - John A. Rogers
- Department of Materials Science and Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
- Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL 60208, USA
- Department of Mechanical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
- Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
- Departments of Chemistry, and Electrical Engineering and Computer Science, McCormick School of Engineering, Northwestern University, Evanston, IL 60208, USA
- Departments of Neurological Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
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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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Nikolaidis PT, de Sousa CV, Knechtle B. Sex difference in long-distance open-water swimming races - does nationality play a role? Res Sports Med 2018; 26:332-344. [PMID: 29508650 DOI: 10.1080/15438627.2018.1447471] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
In open-water swimming events with non-elite swimmers held in the USA, but not in Europe, women were faster than men. We examined the sex difference in elite long-distance open-water swimming races and the role of nationality by investigating 7,468 swimmers competing in 5 km, 10 km and 25 km FINA races held between 2000 and 2016. More men participated in 10 km and 25 km than in 5km races. Men were faster than women and the sex difference was similar in all race distances. Swimming speed was faster for 5km than for 10km, which in turn was faster than 25km. There was a major effect of nationality on swimming speed at 5 km and 10 km, but not at 25km. No dominance of a particular nationality was observed for all race distances. In summary, men were faster than women in all FINA race distances from 5km to 25km but nationality played no role in the sex difference.
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Affiliation(s)
| | - Caio V de Sousa
- b Graduate Program in Physical Education , Catholic University of Brasília , Brazil
| | - Beat Knechtle
- c Institute of Primary Care, University of Zurich , Zurich , Switzerland.,d Gesundheitszentrum St. Gallen , St. Gallen , Switzerland
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Characteristics and Challenges of Open-Water Swimming Performance: A Review. Int J Sports Physiol Perform 2018; 12:1275-1284. [PMID: 28459347 DOI: 10.1123/ijspp.2017-0230] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
CONTEXT Although the popularity of open-water swimming (OWS) events has significantly increased in the last decades, specific studies regarding performance of elite or age-group athletes in these events are scarce. PURPOSE To analyze the existing literature on OWS. METHODS Relevant literature was located via computer-generated citations. During August 2016, online computer searches on PubMed and Scopus databases were conducted to locate published research. RESULTS The number of participants in ultraendurance swimming events has substantially increased in the last 10 y. In elite athletes there is a higher overall competitive level of women than of men. The body composition of female athletes (different percentage and distribution of fat tissue) shows several advantages (more buoyancy and less drag) in aquatic conditions that determine the small difference between males and females. The main physiological characteristics of open-water swimmers (OW swimmers) are the ability to swim at high percentage of [Formula: see text] (80-90%) for many hours. Furthermore, to sustain high velocity for many hours, endurance swimmers need a high propelling efficiency and a low energy cost. CONCLUSION Open-water races may be characterized by extreme environmental conditions (water temperature, tides, currents, and waves) that have an overall impact on performance, influencing tactics and pacing. Future studies are needed to study OWS in both training and competition.
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Krabak BJ, Parker KM, DiGirolamo A. Exercise-Associated Collapse: Is Hyponatremia in Our Head? PM R 2017; 8:S61-8. [PMID: 26972268 DOI: 10.1016/j.pmrj.2015.10.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 09/25/2015] [Accepted: 10/04/2015] [Indexed: 11/18/2022]
Abstract
Exercise-associated hyponatremia (EAH) is one of the most common causes of exercise-associated collapse. The primary pathogenesis of EAH is largely the result of excessive fluid intake but is influenced by other factors, including hormonal abnormalities (ie, inappropriate arginine vasopressin secretion), renal abnormalities, and mobilization of sodium stores. Early recognition of EAH is crucial to appropriate treatment, because symptoms are varied and may be confused with other causes of exercise-associated collapse. Onsite testing of [Na+] will confirm the diagnosis but is not always available. Rapid treatment of EAH will depend upon the type and severity of symptoms. Treatment protocols range from fluid restriction or oral hypertonic fluids for mild symptoms to intravenous hypertonic fluids for more severe symptoms. Preventative strategies should emphasize fluid consumption based on thirst and athlete/coach/staff education regarding proper hydration practices.
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Affiliation(s)
- Brian J Krabak
- Rehabilitation, Orthopedics and Sports Medicine, University of Washington and Seattle Children's Sports Medicine, 3800 Montlake Boulevard NE, Box 354060, Seattle, WA 98105; and University of Washington and Seattle University(∗).
| | - Kelsey M Parker
- University of Washington and Seattle Children's Sports Medicine, Seattle, WA(†)
| | - Anthony DiGirolamo
- University of Washington and Seattle Children's Sports Medicine, Seattle, WA(‡)
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Knechtle B, Nikolaidis PT, Rosemann T, Rüst CA. Performance trends in 3000 m open-water age group swimmers from 25 to 89 years competing in the FINA World Championships from 1992 to 2014. Res Sports Med 2016; 25:67-77. [PMID: 27868433 DOI: 10.1080/15438627.2016.1258647] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
We investigated trends in participation, performance and sex difference in performance in 3000 m freestyle in age groups swimmers (25-29 to 85-89 years) competing in the Fédération Internationale de Natation World Masters Championships between 1992 and 2014. During this period, participation increased in women and men. Women and men improved race times across years in all age groups. Women were slower in age groups 25-29 to 70-74 years. In age groups 75-79 and 85-89 years, however, race times were similar for both women and men. Sex difference in performance remained unchanged across years. In summary, performance improved across years in all age groups, men were faster than women up to the age group 70-74 years and women were not able to reduce the sex difference in performance to men across years. For athletes and coaches, an increase in participation and a continuous improvement in performance can be expected in these age group athletes.
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Affiliation(s)
- Beat Knechtle
- a Gesundheitszentrum St. Gallen , St. Gallen , Switzerland.,b Institute of Primary Care , University of Zurich , Zurich , Switzerland
| | - Pantelis T Nikolaidis
- c Department of Physical and Cultural Education , Hellenic Army Academy , Athens , Greece
| | - Thomas Rosemann
- b Institute of Primary Care , University of Zurich , Zurich , Switzerland
| | - Christoph A Rüst
- b Institute of Primary Care , University of Zurich , Zurich , Switzerland
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Jones B, Till K, King R, Gray M, OʼHara J. Are Habitual Hydration Strategies of Female Rugby League Players Sufficient to Maintain Fluid Balance and Blood Sodium Concentration During Training and Match-Play? A Research Note From the Field. J Strength Cond Res 2016; 30:875-80. [PMID: 26332779 DOI: 10.1519/jsc.0000000000001158] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Limited data exist on the hydration status of female athletes, with no data available on female rugby players. The objective of this study was to investigate the habitual hydration status on arrival, sweat loss, fluid intake, sweat Na loss, and blood [Na+] during field training and match-play in 10 international female rugby league players. Urine osmolality on arrival to match-play (382 ± 302 mOsmol·kg(-1)) and training (667 ± 260 mOsmol·kg(-1)) was indicative of euhydration. Players experienced a body mass loss of 0.50 ± 0.45 and 0.56 ± 0.53% during match-play and training, respectively. During match-play, players consumed 1.21 ± 0.43 kg of fluid and had a sweat loss of 1.54 ± 0.48 kg. During training, players consumed 1.07 ± 0.90 kg of fluid, in comparison with 1.25 ± 0.83 kg of sweat loss. Blood [Na+] was well regulated (Δ-0.7 ± 3.4 and Δ-0.4 ± 2.6 mmol·L(-1)), despite sweat [Na+] of 47.8 ± 5.7 and 47.2 ± 6.3 mmol·L(-1) during match-play and training. The findings of this study show mean blood [Na+] that seems to be well regulated despite losses of Na in sweat and electrolyte-free fluid consumption. For the duration of the study, players did not experience a body mass loss (dehydration >2%) indicative of a reduction in exercise performance, thus habitual hydration strategies seem adequate. Practitioners should evaluate the habitual hydration status of athletes to determine whether interventions above habitual strategies are warranted.
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Affiliation(s)
- Ben Jones
- Research Institute Sport, Physical Activity and Leisure, Leeds Beckett University, Leeds, West Yorkshire, United Kingdom
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15
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Sedgwick PE, Wortley GC, Wright JM, Asplund C, William OR, Usman S. Medical Clearance for Desert and Land Sports, Adventure, and Endurance Events. Wilderness Environ Med 2016; 26:S47-54. [PMID: 26617378 DOI: 10.1016/j.wem.2015.09.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 06/12/2015] [Indexed: 11/15/2022]
Abstract
Endurance events are increasing in popularity in wilderness and remote settings, and participants face a unique set of potential risks for participation. The purpose of this article is to outline these risks and allow the practitioner to better guide the wilderness adventurer who is anticipating traveling to a remote or desert environment.
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Affiliation(s)
- Peter E Sedgwick
- Central Maine Sports Medicine (A Clinical Division of CMMC), Lewiston, Maine (Dr Sedgwick).
| | - George C Wortley
- Lynchburg Family Medicine Residency, Lynchburg, Virginia (Dr Wortley)
| | - Justin M Wright
- Department of Family and Community Medicine, Paul L. Foster School of Medicine, El Paso, Texas (Dr Wright)
| | - Chad Asplund
- Family Medicine, Georgia Regents University, Augusta, Georgia (Dr Asplund)
| | - O Roberts William
- Department of Family Medicine and Community Health, University of Minnesota, Minneapolis, Minnesota (Dr Roberts)
| | - Saif Usman
- Primary Care Sports Medicine, Marymount University, MedStar Medical Group, Arlington, Virginia (Dr Usman)
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16
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Abstract
Endurance events are increasing in popularity in wilderness and remote settings, and participants face a unique set of potential risks for participation. The purpose of this article is to outline these risks and allow the practitioner to better guide the wilderness adventurer who is anticipating traveling to a remote or desert environment.
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17
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de Vries GJ, Forger NG. Sex differences in the brain: a whole body perspective. Biol Sex Differ 2015; 6:15. [PMID: 26279833 PMCID: PMC4536872 DOI: 10.1186/s13293-015-0032-z] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 07/28/2015] [Indexed: 12/29/2022] Open
Abstract
Most writing on sexual differentiation of the mammalian brain (including our own) considers just two organs: the gonads and the brain. This perspective, which leaves out all other body parts, misleads us in several ways. First, there is accumulating evidence that all organs are sexually differentiated, and that sex differences in peripheral organs affect the brain. We demonstrate this by reviewing examples involving sex differences in muscles, adipose tissue, the liver, immune system, gut, kidneys, bladder, and placenta that affect the nervous system and behavior. The second consequence of ignoring other organs when considering neural sex differences is that we are likely to miss the fact that some brain sex differences develop to compensate for differences in the internal environment (i.e., because male and female brains operate in different bodies, sex differences are required to make output/function more similar in the two sexes). We also consider evidence that sex differences in sensory systems cause male and female brains to perceive different information about the world; the two sexes are also perceived by the world differently and therefore exposed to differences in experience via treatment by others. Although the topic of sex differences in the brain is often seen as much more emotionally charged than studies of sex differences in other organs, the dichotomy is largely false. By putting the brain firmly back in the body, sex differences in the brain are predictable and can be more completely understood.
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Affiliation(s)
- Geert J. de Vries
- Neuroscience Institute, Georgia State University, P.O. Box 5030, Atlanta, GA 30302-5030 USA
| | - Nancy G. Forger
- Neuroscience Institute, Georgia State University, P.O. Box 5030, Atlanta, GA 30302-5030 USA
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Hew-Butler T, Rosner MH, Fowkes-Godek S, Dugas JP, Hoffman MD, Lewis DP, Maughan RJ, Miller KC, Montain SJ, Rehrer NJ, Roberts WO, Rogers IR, Siegel AJ, Stuempfle KJ, Winger JM, Verbalis JG. Statement of the Third International Exercise-Associated Hyponatremia Consensus Development Conference, Carlsbad, California, 2015. Clin J Sport Med 2015; 25:303-20. [PMID: 26102445 DOI: 10.1097/jsm.0000000000000221] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Tamara Hew-Butler
- *Exercise Science Program, Oakland University, Rochester, Michigan; †Division of Nephrology, University of Virginia Health System, Charlottesville, Virginia; ‡Department of Sports Medicine, West Chester University, West Chester, Pennsylvania; §The Vitality Group, Chicago, Illinois; ¶Department of Physical Medicine and Rehabilitation, VA Northern California Health Care System and University of California Davis, Sacramento, California; ‖Family Medicine Residency Program, Via Christi Hospitals Wichita, Inc, Wichita, Kansas; **Department of Sport and Exercise Nutrition, Loughborough University, Leicestershire, United Kingdom; ††Athletic Training Program, Central Michigan University, Mount Pleasant, Michigan; ‡‡Military Nutrition Division, United States Army Research Institute of Environmental Medicine, Natick, Massachusetts; §§School of Physical Education, Sport and Exercise Science, University of Otago, Dunedin, New Zealand; ¶¶Department of Family Medicine and Community Health, University of Minnesota, Minneapolis, Minnesota; ‖‖Department of Emergency Medicine, St John of God Murdoch Hospital and University of Notre Dame, Perth, Western Australia; ***Department of Internal Medicine, Harvard Medical School, Boston, Massachusetts; †††Health Sciences Department, Gettysburg College, Gettysburg, Pennsylvania; ‡‡‡Department of Family Medicine, Loyola University Chicago Stritch School of Medicine, Chicago, Illinois; and §§§Department of Endocrinology and Metabolism, Georgetown University Medical Center, Washington, District of Columbia
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Physiopathological, Epidemiological, Clinical and Therapeutic Aspects of Exercise-Associated Hyponatremia. J Clin Med 2014; 3:1258-75. [PMID: 26237602 PMCID: PMC4470181 DOI: 10.3390/jcm3041258] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 10/24/2014] [Accepted: 10/24/2014] [Indexed: 11/25/2022] Open
Abstract
Exercise-associated hyponatremia (EAH) is dilutional hyponatremia, a variant of inappropriate antidiuretic hormone secretion (SIADH), characterized by a plasma concentration of sodium lower than 135 mEq/L. The prevalence of EAH is common in endurance (<6 hours) and ultra-endurance events (>6 hours in duration), in which both athletes and medical providers need to be aware of risk factors, symptom presentation, and management. The development of EAH is a combination of excessive water intake, inadequate suppression of the secretion of the antidiuretic hormone (ADH) (due to non osmotic stimuli), long race duration, and very high or very low ambient temperatures. Additional risk factors include female gender, slower race times, and use of nonsteroidal anti-inflammatory drugs. Signs and symptoms of EAH include nausea, vomiting, confusion, headache and seizures; it may result in severe clinical conditions associated with pulmonary and cerebral edema, respiratory failure and death. A rapid diagnosis and appropriate treatment with a hypertonic saline solution is essential in the severe form to ensure a positive outcome.
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Exercise-associated hyponatremic encephalopathy in an endurance open water swimmer. Wilderness Environ Med 2014; 26:59-61. [PMID: 25443755 DOI: 10.1016/j.wem.2014.07.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 07/18/2014] [Accepted: 07/21/2014] [Indexed: 11/22/2022]
Abstract
Exercise-associated hyponatremia and its more serious form, known as exercise-associated hyponatremic encephalopathy, are recognized as some of the most important medical problems seen in a variety of different forms of endurance exercise. We describe a case of exercise-associated hyponatremic encephalopathy presenting as altered conscious state and seizures in a woman who had completed a 20-km open ocean swim. Her serum sodium measured approximately 1 hour after her seizure was 119 mmol/L on point-of-care testing. With ongoing critical care support and the use of hypertonic saline, she was able to be extubated the next day, neurologically intact, and ultimately was discharged from hospital without neurological sequelae. This case emphasizes both the importance of considering exercise-associated hyponatremic encephalopathy as a cause of neurological impairment in all athletes and the pivotal role of hypertonic saline in the treatment of this condition.
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Wild S, Rüst CA, Rosemann T, Knechtle B. Changes in sex difference in swimming speed in finalists at FINA World Championships and the Olympic Games from 1992 to 2013. BMC Sports Sci Med Rehabil 2014; 6:25. [PMID: 25120914 PMCID: PMC4129435 DOI: 10.1186/2052-1847-6-25] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2014] [Accepted: 06/19/2014] [Indexed: 11/11/2022]
Abstract
Background This study investigated swimming speeds and sex differences of finalists competing at the Olympic Games (i.e. 624 female and 672 male athletes) and FINA World Championships (i.e. 990 women and 1008 men) between 1992 and 2013. Methods Linear, non-linear and multi-level regression models were used to investigate changes in swimming speeds and sex differences for champions and finalists. Results Regarding finalists in FINA World Championships and Olympic Games, swimming speed increased linearly in both women and men in all disciplines and race distances. Male world champions’ swimming speed remained stable in 200 m butterfly, 400 m, 800 m and 1,500 m freestyle. Considering women, swimming speed remained unchanged in 50 m and 400 m freestyle. In the Olympic Games, swimming speed of male champions remained unchanged in 200 m breaststroke, 50 m, 400 m, 800 m and 1,500 m freestyle. Female Olympic champions’ swimming speed remained stable in 100 m and 200 m backstroke, 100 m butterfly, 200 m individual medley, 50 m and 200 m freestyle. Evaluating sex differences between finalists in FINA World Championships, results showed a linear decrease in 100 m breaststroke and 200 m butterfly and a non-linear increase in 100 m backstroke. In finals at the Olympic Games, the sex difference decreased linearly for 100 m backstroke, 400 m and 800 m freestyle. However, a linear increase for 200 m butterfly can be reported. Considering Olympic and world champions, the sex difference remained stable in all disciplines and race distances. Conclusion Swimming speed of the finalists at the Olympic Games and FINA World Championships increased linearly. The top annual female swimmers increased swimming speed rather at longer race distances (i.e. 800 m and 1,500 m freestyle, 200 m butterfly, and 400 m individual medley), whereas the top annual male swimmers increased it rather at shorter race distances (i.e. 100 m and 200 m freestyle, 100 m butterfly, and 100 m breaststroke). Sex difference in swimming was unchanged in Olympic and world champions. Finalists and champions at the Olympic Games and FINA World Championships reduced the sex difference with increasing race distance.
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Affiliation(s)
- Stefanie Wild
- Institute of General Practice and for Health Services Research, University of Zurich, Zurich, Switzerland
| | - Christoph Alexander Rüst
- Institute of General Practice and for Health Services Research, University of Zurich, Zurich, Switzerland
| | - Thomas Rosemann
- Institute of General Practice and for Health Services Research, University of Zurich, Zurich, Switzerland
| | - Beat Knechtle
- Institute of General Practice and for Health Services Research, University of Zurich, Zurich, Switzerland ; Gesundheitszentrum St. Gallen, Vadianstrasse 26, 9001 St. Gallen, Switzerland
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Vogt P, Rüst CA, Rosemann T, Lepers R, Knechtle B. Analysis of 10 km swimming performance of elite male and female open-water swimmers. SPRINGERPLUS 2013; 2:603. [PMID: 24324922 PMCID: PMC3853191 DOI: 10.1186/2193-1801-2-603] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Accepted: 11/05/2013] [Indexed: 11/24/2022]
Abstract
This study investigated trends in performance and sex difference in swimming speed of elite open-water swimmers at FINA 10 km competitions (i.e. World Cup races, European Championships, World Championships and Olympic Games). Swimming speed and sex difference in swimming speed of the fastest and the top ten women and men per event competing at 10 km open-water races between 2008 and 2012 were analysed using single and multi-level regression analyses. A total of 2,591 swimmers (i.e. 1,120 women and 1,471 men) finished 47 races. Swimming speed of the fastest women (1.35 ± 0.9 m/s) and men (1.45 ± 0.10 m/s) showed no changes across years. The mean sex difference in swimming speed for the fastest swimmers was 6.8 ± 2.5%. Swimming speed of the top ten female swimmers per event was 1.34 ± 0.09 m/s and remained stable across the years. The top ten male swimmers per event showed a significant decrease in swimming speed over time, even though swimming speed in the first race (i.e. January 2008, 1.40 ± 0.0 m/s) was slower than the swimming speed in the last race (i.e. October 2012, 1.50 ± 0.0 m/s) (P < 0.05). To summarize, swimming performances remained stable for the fastest elite open-water swimmers at 10 km FINA competitions between 2008 and 2012, while performances of the top ten men tended to decrease. The sex difference in swimming speed in elite ultra-swimmers (~7%) appeared smaller compared to other ultra-distance disciplines such as running. Further studies should examine how body shape and physiology of elite open-water ultra-distance swimmers influence performances.
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Affiliation(s)
- Pascale Vogt
- Facharzt FMH für Allgemeinmedizin, Gesundheitszentrum St. Gallen, Vadianstrasse 26, 9001 St. Gallen, Switzerland
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Dion T, Savoie FA, Asselin A, Gariepy C, Goulet EDB. Half-marathon running performance is not improved by a rate of fluid intake above that dictated by thirst sensation in trained distance runners. Eur J Appl Physiol 2013; 113:3011-20. [DOI: 10.1007/s00421-013-2730-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Accepted: 09/14/2013] [Indexed: 10/26/2022]
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Rüst CA, Knechtle B, Rosemann T, Lepers R. Women reduced the sex difference in open-water ultra-distance swimming [Formula: see text] La Traversée Internationale du Lac St-Jean, 1955-2012. Appl Physiol Nutr Metab 2013; 39:270-3. [PMID: 24476486 DOI: 10.1139/apnm-2013-0222] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In La Traversée Internationale du Lac St-Jean, held between 1955 and 2012 in Canada, the fastest women (r(2) = 0.61, p < 0.0001) and men (r(2) = 0.66, p < 0.0001) improved swimming speed over the years but the sex difference remained unchanged at 8.8% ± 5.6% (r(2) = 0.069, p = 0.065). Annually, for the 3 fastest swimmers, both women (r(2) = 0.53, p < 0.0001) and men (r(2) = 0.71, p < 0.0001) improved swimming speed between 1973 and 2012 and the sex difference decreased (r(2) = 0.29, p = 0.0016) from 14.4% ± 11.0% (1973) to 3.7% ± 1.4% (2012).
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Affiliation(s)
- Christoph A Rüst
- a Institute of General Practice and for Health Services Research, University of Zurich, Zurich, Switzerland
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Fischer G, Knechtle B, Rüst CA, Rosemann T. Male swimmers cross the English Channel faster than female swimmers. Scand J Med Sci Sports 2012; 23:e48-55. [PMID: 23121394 DOI: 10.1111/sms.12008] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/28/2012] [Indexed: 10/27/2022]
Affiliation(s)
- G. Fischer
- Institute of General Practice and Health Services Research; University of Zurich; Zurich; Switzerland
| | | | - C. A. Rüst
- Institute of General Practice and Health Services Research; University of Zurich; Zurich; Switzerland
| | - T. Rosemann
- Institute of General Practice and Health Services Research; University of Zurich; Zurich; Switzerland
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