Initial Fine Control Mechanism of Sweating in Well-Trained Athletes

在环境热中性（23 ℃）和60%相对湿度下，在中度自行车运动（80 W，30 min）期间，测定了有和无长期定期体力活动（运动员：超过8年，至少过去2年为非运动员）的人类受试者胸部和大腿的局部出汗率（Msw）和汗液排出频率（Fsw）。用电容湿度计-通气胶囊法记录出汗率和汗液排出模式。在MacLab/8 e硬件平台上，利用Chafv 3. 5软件中的微分函数，对原始出汗波形进行微分，得到不同运动员的排汗微分波形，除VO 2 max外，运动员与非运动员的各项生理指标无显著差异，运动员的Msw有降低趋势。与非运动员相比，运动员的Msw随Fsw的增加而增加的幅度明显较小，Fsw也控制在明显较低的速率。运动期间运动员的平均Fsw（每分钟汗液排出量）显著低于非运动员。运动员Fsw与平均体温（mTh）的回归系数显著大于非运动员。运动开始后，平均皮肤温度（mTs）暂时下降，这在运动员中不太明显。运动结束时，运动员的mTs显著升高，而非运动员的mTs则无显著变化。结果表明，长期的体育训练可改善皮肤的循环热传递，使神经对汗液排出的控制更加分级化，并有降低出汗率的趋势。Fsw与平均体温之间的相关系数，局部出汗率和Fsw在微分波中大于原始波。

Local sweat rates (Msw) at the chest and thigh and the frequency of sweat expulsions (Fsw) were determined in human subjects with and without long-term regular physical activities (athlctes : for more than 8 years, non-athletes at least for the past 2 years) during moderate bicycle exercise (80 W for 30 min) at ambient thermoneutrality (23ﾟC) and 60% relative humidity. The sweat rate and sweat expulsion patterns were recorded by a capacitance hygrometer-ventilated capsule method. The differential waves of sweat expulsion were derived from the original sweating waves by using the differential function in software (Chaff v3.5) with the MacLab hardware unit (MacLab/8e).There was no significant difference in the physical characteristics between athletes and non-athletes, except for VO2max.There was a tendency of Msw to be lower in athletes. The rise of Msw with increasing Fsw was significantly less steep and Fsw was also controlled at a significantly lower rate in athletes as compared to non-athletes. The average Fsw (sweat expulsions per min) during exercise period was significantly lower in athletes than in non-athletes. A regression coefficient between Fsw and mean body temperature (mTh) for athletes was significantly larger than the coefficient for non-athletes. The start of exercise was followed by a temporary decrease in mean skin temperature (mTs) which was less distinct in athletes. The rise in mTs at thc end of exercise was significant in athletes but not in non-athletes.The results indicate that long-term physical training leads to improved circulatory heat transfer to the skin and to a more graded nervous control of sweat expulsion and, further, tends to reduce the rate of sweating.The correlation coefficients in the relationships between Fsw and mean body temperature, local sweat rate and Fsw were larger in the differential waves than in the original waves.