Quick Search:

uzh logo
Browse by:

Zurich Open Repository and Archive

Permanent URL to this publication: http://dx.doi.org/10.5167/uzh-49162

Wagner, S; Knechtle, B; Knechtle, P; Rüst, C A; Rosemann, T (2012). Higher prevalence of exercise-associated hyponatremia in female than in male open-water ultra-endurance swimmers: the 'Marathon-Swim' in Lake Zurich. European Journal of Applied Physiology, 112(3):1095-1106.

[img]Published Version
PDF - Registered users only
View at publisher


We investigated the prevalence of exercise-associated hyponatremia (EAH) in 25 male and 11 female open-water ultra-endurance swimmers participating in the 'Marathon-Swim' in Lake Zurich, Switzerland, covering a distance of 26.4 km. Changes in body mass, fat mass, skeletal muscle mass, total body water, urine specific gravity, plasma sodium concentration [Na(+)] and haematocrit were determined. Two males (8%) and four females (36%) developed EAH where one female was symptomatic with plasma sodium [Na(+)] of 127 mmol/L. Body mass and plasma [Na(+)] decreased (p < 0.05). The changes in body mass correlated in both male and female swimmers to post-race plasma [Na(+)] (r = -0.67, p = 0.0002 and r = -0.80, p = 0.0034, respectively) and changes in plasma [Na(+)] (r = -0.68, p = 0.0002 and r = -0.79, p = 0.0039, respectively). Fluid intake was neither associated with changes in body mass, post-race plasma [Na(+)] or the change in plasma [Na(+)]. Sodium intake showed no association with either the changes in plasma [Na(+)] or post-race plasma [Na(+)]. We concluded that the prevalence of EAH was greater in female than in male open-water ultra-endurance swimmers.


20 citations in Web of Science®
21 citations in Scopus®
Google Scholar™



0 downloads since deposited on 22 Aug 2011
0 downloads since 12 months

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:04 Faculty of Medicine > University Hospital Zurich > Institute of General Practice
Dewey Decimal Classification:610 Medicine & health
Deposited On:22 Aug 2011 06:35
Last Modified:05 Apr 2016 14:58
Publisher DOI:10.1007/s00421-011-2070-5
PubMed ID:21748367

Users (please log in): suggest update or correction for this item

Repository Staff Only: item control page