Martineaud J P, Raynaud J, Duhaze P, Vieillefond H
J Physiol (Paris). 1976;72(2):233-47.
Three groups of subjects, Europeans without any heat acclimation (called EE), Europeans after 3 weeks of acclimatization in India (EI), and Indians in their natural environment (II) were studied during exposure to an ambient temperature of 33 degrees C. Hand blood flow (Q), rectal temperature (Tre), mean cutaneous temperature (Tsk) were simultaneously recorded at rest and during 2 periods of muscular exercise (0.44 and 0.7 Vo2 max) of 35 mn duration. The results showed (1) at rest, Q was very high in EE, quite low in both EI and II; (2) at the onset of exercise, a hand vasoconstriction was observed in all cases; (3) during exercise, there was a progressive increase of Q until 200% maximum above rest values; (4) at the end of exercise, Q was proportional to the intensity of the exercise for each group and inversely proportional to the duration of heat exposure, the highest Q was observed in EE, the lowest in II and an intermediate value for EI close to the latter). These differences in hand blood flow could not be explained by differences in deep and/or superficial temperatures between subjects. Thus, during chronic heat exposure, there is, especially for an exercising man, a progressive modification of heat transport in the body: that is, a reduction of skin perfusion and a greater Tre-Tsk difference which are both adaptative responses. The value of hand blood flow as an estimation of whole superficial circulation is discussed.
研究了三组受试者，即未经过任何热适应的欧洲人（称为EE组）、在印度经过3周适应的欧洲人（EI组）以及处于自然环境中的印度人（II组），他们暴露于33摄氏度的环境温度下。在静息状态以及两个持续35分钟的肌肉运动阶段（分别为0.44和0.7最大摄氧量）期间，同时记录手部血流量（Q）、直肠温度（Tre）和平均皮肤温度（Tsk）。结果显示：（1）静息时，EE组的Q值非常高，EI组和II组的Q值相当低；（2）运动开始时，所有受试者均出现手部血管收缩；（3）运动期间，Q值逐渐增加，直至比静息值高出200%；（4）运动结束时，每组的Q值与运动强度成正比，与热暴露持续时间成反比，EE组的Q值最高，II组的Q值最低，EI组的值介于两者之间且更接近II组。受试者手部血流量的这些差异无法用深部和/或体表温度的差异来解释。因此，在长期热暴露期间，尤其是对于运动中的人而言，身体的热传递会逐渐发生改变：即皮肤灌注减少以及Tre - Tsk差值增大，这两者都是适应性反应。文中还讨论了将手部血流量作为整体体表循环估计值的价值。
