Effects of two kinds of clothing made from hydrophobic and hydrophilic fabrics on local sweating rates at an ambient temperature of 37 degrees C.

The purpose of this study was to find the effects of clothing made from hydrophobic and hydrophilic fabrics on the sweating physiology in environmental conditions where only the mechanisms of wet heat loss could occur. A comparison was made of the local sweat rates from the forearm and their related physiological parameters between polyester (E) and cotton (C) clothing at an ambient temperature (Ta) of 37 degrees C. Six female students, aged from 21 to 28 years, served as subjects. The subjects wore clothing made from either fabric E or fabric C and rested quietly for 60 min in a chair mounted on the bed scale under the influences of environmental conditions of 37 degrees C and 60% relative humidity (rh) with an air velocity of 0.1 m.s-1. The major findings are summarized as follows: (1) Local sweat rates were distinctly higher in E than in C in five out of six female subjects. (2) Clothing surface temperatures at the chest level were significantly higher in C than in E. (3) The positive relationship between local sweat rates and mean skin temperature (Tsk) existed both in E and in C. However, the local sweat rates were mostly higher in E under the influences of the same Tsk. These results are discussed in terms of thermal physiology and clothing sciences. It was concluded that the different properties of moisture absorbency between E and C could play a role for sweating physiology in the environmental conditions where only the mechanism of wet heat loss could occur.