Relevance of thermal comfort in location to the whole body in terms of cortisol and salivary α-amylase

这项研究的目的是通过唾液中的皮质醇和α-淀粉酶活性，从实验上讨论局部热舒适与全身的相关性。16名年轻的日本女性受试者参加了实验。至于目标位置，选择了躯干、手臂和大腿三个身体区域，它们的身体表面积几乎相同，约为17%。局部热舒适极限与局部皮肤湿润度的关系因个体位置不同而不同。手臂舒适度为0.16±0.08，大腿舒适度为0.17±0.10。躯干舒适度为0.28±0.16，明显高于四肢舒适度。结果表明，皮肤湿润度保持在0.22±0.10范围内，即使局部皮肤湿润度远高于局部舒适值，也不会引起全身热不适。唾液中的皮质醇不反映全身的热舒适感，而淀粉酶活性反映了这一点。当全身感觉轻微不适时，唾液淀粉酶活性随着热舒适度的降低而显着升高。

The aim of this study is to discuss experimentally relevance of thermal comfort in location to the whole body in terms of cortisol and α-amylase activity in saliva. Sixteen young Japanese female subjects participated in the experiments. As for the target locations, three body regions of trunk, arms, and thighs were selected all with almost identical body surface area of about 17 %. The relation of the local thermal comfort limit with the local skin wettednesses differed depending upon the individual location. The comfort limit in the arms and the thighs were 0.16±0.08 and 0.17±0.10, respectively. On the other hand, the comfort limit in the trunk was 0.28±0.16, which was found to be significantly larger than those of limbs. It was observed that thermal discomfort in the whole body wasn't induced if its skin wettedness stayed within 0.22±0.10, even if the local skin wettedness indicated much higher value than the local comfort limit. Cortisol in saliva did not reflect thermal comfort sensation in the whole body, while amylase activity did. The salivary amylase activity remarkably increased with decreasing thermal comfort when the whole body felt slightly discomfort.