钠补充剂和气候对超长马拉松跑步期间电解质失衡的影响。

Effect of Sodium Supplements and Climate on Dysnatremia During Ultramarathon Running.

机构信息

Department of Emergency Medicine, Stanford University School of Medicine, Palo Alto, California.

Department of Computational Science, University of Colorado, Boulder, Colorado.

出版信息

Clin J Sport Med. 2021 Nov 1;31(6):e327-e334. doi: 10.1097/JSM.0000000000000832.

DOI:10.1097/JSM.0000000000000832

PMID:32097177

Abstract

OBJECTIVE

Analyze the effect of sodium supplementation, hydration, and climate on dysnatremia in ultramarathon runners.

DESIGN

Prospective observational study.

SETTING

The 2017 80 km (50 mile) stage of the 250 km (150 mile) 6-stage RacingThePlanet ultramarathon in 2017 Chilean, Patagonian, and 2018 Namibian, Mongolian, and Chilean deserts.

PARTICIPANTS

All race entrants who could understand English were invited to participate, with 266 runners enrolled, mean age of 43 years (± 9), 61 (36%) females, average weight 74 kg (± 12.5), and average race time 14.5 (± 4.1) hours. Post-race sodium collected on 174 (74%) and 164 (62%) participants with both the blood sample and post-race questionnaire.

INTERVENTION

Weight change and finish line serum sodium levels were gathered.

MAIN OUTCOME MEASURES

Incidence of exercise-associated hyponatremia (EAH; <135 mmol·L-1) and hypernatremia (>145 mmol·L-1) by sodium ingestion and climate.

RESULTS

Eleven (6.3%) runners developed EAH, and 30 (17.2%) developed hypernatremia. Those with EAH were 14 kg heavier at baseline, had significantly less training distances, and averaged 5 to 6 hours longer to cover 50 miles (80 km) than the other participants. Neither rate nor total ingested supplemental sodium was correlated with dysnatremia, without significant differences in drinking behaviors or type of supplement compared with normonatremic runners. Hypernatremic runners were more often dehydrated [8 (28%), -4.7 kg (± 9.8)] than EAH [4 (14%), -1.1 kg (± 3.8)] (P < 0.01), and EAH runners were more frequently overhydrated (6, 67%) than hypernatremia (1, 11%) (P < 0.01). In the 98 (56%) runners from hot races, there was EAH OR = 3.5 [95% confidence interval (CI), 0.9-25.9] and hypernatremia OR = 8.8 (95% CI, 2.9-39.5) compared with cold races.

CONCLUSIONS

This was the first study to show that hot race climates are an independent risk factor for EAH and hypernatremia. Sodium supplementation did not prevent EAH nor cause hypernatremia. Longer training distances, lower body mass, and avoidance of overhydration were shown to be the most important factors to prevent EAH and avoidance of dehydration to prevent hypernatremia.

摘要

目的

分析钠补充、水合作用和气候对超长马拉松运动员中电解质紊乱的影响。

设计

前瞻性观察研究。

地点

2017 年智利、巴塔哥尼亚和 2018 年纳米比亚、蒙古和智利沙漠 250 公里（150 英里）6 阶段赛车星球超长马拉松的 80 公里（50 英里）阶段。

参与者

所有能理解英语的参赛者均被邀请参加，共有 266 名参赛者，平均年龄 43 岁（±9），61 名女性（36%），平均体重 74 公斤（±12.5），平均比赛时间 14.5 小时（±4.1）。赛后收集了 174 名（74%）和 164 名（62%）参与者的血钠样本和赛后问卷。

干预

体重变化和终点线血清钠水平。

主要观察指标

根据钠摄入和气候，运动相关低钠血症（EAH；<135 mmol·L-1）和高钠血症（>145 mmol·L-1）的发生率。

结果

11 名（6.3%）跑步者发生 EAH，30 名（17.2%）发生高钠血症。EAH 患者的基线体重重 14 公斤，训练距离明显减少，与其他参与者相比，平均需要 5 到 6 个小时才能跑完 50 英里（80 公里）。钠摄入量或总摄入量与电解质紊乱均无相关性，与正常钠血症跑步者相比，饮酒行为或补充剂类型无显著差异。高钠血症患者脱水程度更严重[8 例（28%），体重减轻 4.7 公斤（±9.8）]，而 EAH 患者[4 例（14%），体重减轻 1.1 公斤（±3.8）]（P<0.01），EAH 患者更常出现水过多（6 例，67%），而高钠血症患者（1 例，11%）（P<0.01）。在 98 名（56%）来自炎热比赛的参赛者中，与寒冷比赛相比，EAH 的比值比为 3.5（95%置信区间（CI），0.9-25.9），高钠血症的比值比为 8.8（95% CI，2.9-39.5）。