Institute of General Practice and Health Services Research, University of Zurich, Zurich, Switzerland.
Eur J Appl Physiol. 2012 Mar;112(3):1095-106. doi: 10.1007/s00421-011-2070-5. Epub 2011 Jul 12.
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.
我们调查了 25 名男性和 11 名女性公开水域超长距离游泳运动员在瑞士苏黎世湖参加“马拉松游泳”时与运动相关的低钠血症（EAH）的患病率，游泳距离为 26.4 公里。测定了体重、脂肪量、骨骼肌量、总体水量、尿比重、血浆钠浓度[Na(+)]和血细胞比容的变化。有 2 名男性（8%）和 4 名女性（36%）发生了 EAH，其中 1 名女性出现症状，血浆钠[Na(+)]为 127mmol/L。体重和血浆[Na(+)]下降（p<0.05）。男女游泳运动员的体重变化与赛后血浆[Na(+)]（r=-0.67，p=0.0002 和 r=-0.80，p=0.0034）和血浆[Na(+)]变化相关（r=-0.68，p=0.0002 和 r=-0.79，p=0.0039）。液体摄入量与体重变化、赛后血浆[Na(+)]或血浆[Na(+)]变化均无关联。钠摄入量与血浆[Na(+)]变化或赛后血浆[Na(+)]无关联。我们得出结论，女性公开水域超长距离游泳运动员 EAH 的患病率高于男性。
