Abstract
The present experiment aimed to know whether thermophysiological responses varied between two kinds of clothing conditions of wearing hat or no hat in sedentary and lightly exercising women under warm and radiant environments. Tympanic and rectal temperatures increased to smaller extent in hat wearing conditions under the influences of gradual increase of ambient temperature 28 to 35°C and radiant heat gain from two artificial sunshine lamps (400 W × 2). Sweat onset time was also significantly delayed in hat wearing conditions. The rear surface temperature in the head hair was significantly lower in hat wearing conditions. These different responses in tympanic temperature between hat and not hat wearing conditions might be partly explained by the different amounts of counter-current heat exchange between venous blood flowing from head surface through the cranium into the brain and arterial blood ascending to the hypothalamus.
