[The effects of environmental thermal condition on transitional skin temperature of peripheral parts of human hands and feet during exercise].

The effects of environmental temperature on transitional skin temperatures of peripheral parts of human hands and feet were examined during exercise to obtain basic information on thermal characteristics of heat transfer from human body to the environment. Very thin and fat male adults served as subjects who were in contrast regarding fat content. Their skin temperatures were undertaken by thermocouples in a climate chamber. The exercise was made using an ergometer at three stages of the chamber temperatures. The skin temperature of a fat subject's trunk was observed to be lower than that of thin subject due to the insulation of fat in the body. In compensation for less heat transfer from the trunk, the temperatures of peripheral parts of fat subject's hands and feet were higher than that of the thin subject. Moreover, the response of the temperature to the thermal load due to exercise was observed to be quicker. These kinds of variation were considered as due to the increase in blood flow through arteriovenous anastomoses, AVA. It seemed that AVA blood of the thin subject did not increase during resting condition at the environmental temperatures of 10 and 20 degrees C but was accelerated by the thermal load due to exercise. In addition, the response of AVA on the foot seemed to be delayed compared with that on the hand.