不同补水量对最高耐热限的影响

EFFECT OF VARIOUS AMOUNTS OF WATER INTAKE ON THE UPPER LIMIT OF HEAT TOLERANCE

在三球温度指数35.6℃热室内比较了两种饮水量对负重12.5kg步行时最高耐热限的影响。受试者为健康青年男子,分为三组,每组8例。第1组饮水量1500ml,第2、3组各1000ml;第3组步行1h后慢跑1h。热暴露后,第1组直肠温度达39.47℃,心率超过160bPm,都坚持2h试验,恢复较迅速,较好;而第2、3组耐热能力和劳动能力大大下降,生理生化改变显著加剧,因直肠温度达40℃而中止试验者分别占16.7%和87.5%, 耐热时间分别减为116.7min和98.5min。因而受热体力活动时,补充70%出汗量的饮水量比较适宜。

The effect of two different amounts of water intake on the upper limit of heat tolerance during two hours walking with backpack loads of 12.5kg in a hot chamber (WBGT 35.6℃) was observed. The subjects were healthy young males and were divided into three groups with eight subjects in each. Each subject of group 1 drank 1500ml of water, while those of group 2 and 3 drank 1000 ml respectively. Members of group 3 walk one hour first, and ran slowly for another hour. After heat exposure, the rectal temperature of group 1 reached 39.47℃ and heart rate more than 160 bpm. However, all of them could endure the two hour's test and recover more quickly and better. Group 2 and 3 decreased sharply the capability of both heat tolerance and physical exertion, and the physiological and biochemical changes were also much more marked.The test was forced to be stopped, because the rectal temperature reached 40℃ in 16.7% and 87.5% of the members respectively, and the heat-tolerance time reduced to 116.7 min and 98.5 min respectively. So it may be considered that the water replenishment up to 70% of the amount lost in sweat may be suitable.