ArticleJournal of the International Society of Sports Nutrition2014
The prevalence of exercise-associated hyponatremia in 24-hour ultra-mountain bikers, 24-hour ultra-runners and multi-stage ultra-mountain bikers in the Czech Republic.
Article in Journal of the International Society of Sports Nutrition, 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
13 citing papers in PubMed, 23 citations in OpenAlex.
- 24-Hour Ultra-Marathon Running: A Narrative Review of Performance Factors and Physiological Impacts.Sports medicine - open · 2026Review
- Time to Consider Potassium Intake in Saudi: A Cross-Sectional Assessment Using 24 h Urinary Excretion.Nutrients · 2025Article
- Exercise-Associated Hyponatremia: Serum Sodium, Symptomatology, Severity, and Sport Specificity.Open access journal of sports medicine · 2025Review
- What is known about the health effects of non-steroidal anti-inflammatory drug (NSAID) use in marathon and ultraendurance running: a scoping review.BMJ open sport & exercise medicine · 2024Article
- Eating habits and nutritional knowledge among amateur ultrarunners.Frontiers in nutrition · 2023Article
- 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.Medicina (Kaunas, Lithuania) · 2019Review
- Body Composition Changes During a 24-h Winter Mountain Running Race Under Extremely Cold Conditions.Frontiers in physiology · 2019Article
- Incidence of Hyponatremia During a Continuous 246-km Ultramarathon Running Race.Frontiers in nutrition · 2019Article
- Maintained Hydration Status After a 24-h Winter Mountain Running Race Under Extremely Cold Conditions.Frontiers in physiology · 2018Article
- Physiology and Pathophysiology in Ultra-Marathon Running.Frontiers in physiology · 2018Review
- Exercise-Associated Hyponatremia: 2017 Update.Frontiers in medicine · 2017Review
- Reported Hydration Beliefs and Behaviors without Effect on Plasma Sodium in Endurance Athletes.Frontiers in physiology · 2017Article
- Physiopathological, Epidemiological, Clinical and Therapeutic Aspects of Exercise-Associated Hyponatremia.Journal of clinical medicine · 2014Review
Corrections and comments
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Authors and funding
5 authors at 4 institutions in 4 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundTo assess the prevalence of exercise-associated hyponatremia (EAH) in two 24-hour mountain bike (MTB) (R1,R2), one 24-hour running (R3) and one multi-stage MTB (R4) races held in the Czech Republic in a cluster of four cross-sectional studies.
methodsIn 27 ultra-mountain bikers (ultra-MTBers), 12 ultra-runners, and 14 multi-stage MTBers, fluid intake, changes (Δ) in body mass, hematocrit, plasma volume, plasma [Na+], plasma [K+], plasma osmolality, urine [Na+], urine [K+], urine specific gravity, urine osmolality, K+/Na+ ratio in urine, transtubular potassium gradient and glomerular filtration rate were measured and calculated. The use of non-steroidal anti-inflammatory drugs and symptoms of EAH were recorded using post-race questionnaires.
resultsOf the 53 finishers, three (5.7%) developed post-race EAH, thereof one (3.7%) ultra-MTBer, one (8.3%) ultra-runner and one (7.1%) multi-stage MTBer. Plasma [Na+] decreased significantly (p < 0.001) only in R4. Urine osmolality (R1, R3, R4 p < 0.001; R2 p < 0.05) and glomerular filtration rate (p < 0.001) increased, and body mass decreased in all races (p < 0.05). Δ body mass was inversely related to the number of kilometers achieved (p < 0.001) in R2 where better ultra-MTBers tended to lose more weight. Δ body mass (p < 0.001) and %Δ body mass (p = 0.05) were positively related to lower post-race plasma [Na+] in R3 that was associated with increased loss in body mass. Fluid intake was positively related to race performance in R1 and R2 (R1: p = 0.04; R2: p = 0.01) where ultra-MTBers in R1 and R2 who drank more finished ahead of those who drank less. Post-race plasma [Na+] was negatively associated with race performance in ultra-MTBers in R2 (p < 0.05), similarly ultra-runners in R3 (p < 0.05) where finishers with more kilometres had lower post-race plasma [Na+].
conclusionsThe prevalence of EAH in the Czech Republic was no higher compared to existing reports on ultra-endurance athletes in other countries. Lower plasma [Na+] and development of EAH may be attributed to overdrinking, a pituitary secretion of vasopressin, an impaired mobilization of osmotically inactive sodium stores, and/or an inappropriate inactivation of osmotically active sodium.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.