Assuming that the wearing clothes are wet, the drying effect by wearing wet clothes and it's influence on thermal insuration of body temperature were studied. Worn clothes which were studied consisted of jersey cotton underwear and shirt made of various materials such as wool, mixed fiber and synthetic fiber.
　For the testing equipment, a trial heat box of 15 cm square was used, which was controlled with a microcomputer so that the surface of the samples was kept at 36°C.
　The experiments were conducted on the following combination, i. e.,
1) Only the cotton wear was wet and the shirt was dry, and
2) both the cotton wear and the shirt was wet. Both the comsumed electric power and the transfer of water content from the clothes were studied. The environmental condition was kept constantly the temperature to be 20°C, humidity 65% RH, air current 25 cm / sec. The results were as follows :
1) When wearing wet underwear even if the shirt is dry, thermal insuration effect was found to be the poorest, therefore, it is recommended that wearing dry underwear preferably those made of synthetic fiber is especially necessary.
2) In case both the shirt and underweare are wet, those not made of cotton should be worn contacting the skin, especially woollen fiber may result in the best thermal insuration effect.

DESCENTE SPORTS SCIENCE Vol.11/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE