Buono Michael J, Ball Kimberly D, Kolkhorst Fred W
School of Exercise and Nutritional Sciences, San Diego State University, San Diego, California 92182, USA.
J Appl Physiol (1985). 2007 Sep;103(3):990-4. doi: 10.1152/japplphysiol.00015.2007. Epub 2007 Jun 28.
The purpose of this study was to determine the effect of active heat acclimation on the sweat osmolality and sweat sodium ion concentration vs. sweat rate relationship in humans. Eight healthy male volunteers completed 10 days of exercise in the heat. The mean exercising heart rate and core temperature were significantly decreased (P < 0.05) by 18 beats/min and 0.6 degrees C, respectively, following heat acclimation. Furthermore, sweat osmolality and the sweat sodium ion concentration vs. sweat rate relationships were shifted to the right. Specifically, the slopes of the relationships were not affected by heat acclimation. Rather, heat acclimation significantly reduced the y-intercepts of the sweat osmolality and sweat sodium relationships with sweat rate by 28 mosmol/kgH(2)O and 15 mmol/l, respectively. Thus there was a significantly lower sweat sodium ion concentration for a given sweat rate following heat acclimation. These results suggest that heat acclimation increases the sodium ion reabsorption capacity of the human eccrine sweat gland.
本研究的目的是确定主动热适应对人体汗液渗透压、汗液钠离子浓度与出汗率关系的影响。八名健康男性志愿者在高温环境下完成了为期10天的锻炼。热适应后，平均运动心率和核心体温分别显著降低（P<0.05），降低幅度为每分钟18次心跳和0.6摄氏度。此外，汗液渗透压以及汗液钠离子浓度与出汗率的关系曲线向右移动。具体而言，这些关系的斜率不受热适应的影响。相反，热适应显著降低了汗液渗透压和汗液钠离子浓度与出汗率关系曲线的y轴截距，分别降低了28毫摩尔/千克H₂O和15毫摩尔/升。因此，热适应后在给定出汗率下汗液钠离子浓度显著降低。这些结果表明，热适应提高了人体外分泌汗腺对钠离子的重吸收能力。
