Abstract
We proposed a numerical index for evaluating human heat tolerance which is practically useful. The adaptive changes in heat tolerance of unacclimatized subjects during short-term heat acclimatization could be evaluated by this index. The present investigation was performed to examine whether or not our index can reflect effects on heat tolerance of a long-term acclimatization as seen in subtropical natives. Nineteen young male residents born and raised in Okinawa (subtropical zone), 18 male residents born in the Japan Main Islands (temperate zone) but moved to Okinawa and 25 male students in Kyoto (temperate zone) were chosen to be subjects. Their age were from 19 to 29 years. Sweating reaction was examined for 60 min in summer, by immersing legs in stirring water of 42°C by using a mobile climatic chamber of 30°C with 70 RH. Local sweat samples from the chest and back were collected at 15 min interval by the filter paper method. Sweating reaction of the residents born and raised in Okinawa was characterized by smaller volume of sweating and lower salt concentration in sweat, while the rise in rectal temperature and increase in heart rate differ less between the three groups. It is concluded that residents born and raised in Okinawa showed higher heat tolerance than the other two groups when assessed by our factorial index method.
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ADOLPH, E.F. (1946): The initiation of sweating in response to heat. Amer. J. Physiol., 145: 710–715.
BASS, D.E. (1963): Thermoregulatory and circulatory adjustments during acclimation to heat in man. In: Temperature, its Measurement and Control in Science and Industry. C.M. Herzfeld (ed.). Reinhold, New York, 3: 229–305.
BELDING, H.S. and HATCH, T.F. (1963): Relation of skin temperature to acclimation and tolerance to heat. Fed. Proc., 22: 881–883.
BELDING, H.S. and HERTING, B.A. (1967): Pittsburgh Bath Test. Comparative Methodology for Heat Tolerance Testing. A Cooperative International Study, US Dept. of HEW, Public Health Service, Natl. Center for Urban and Indust. Health, Cincinnati, Ohio, 168–186.
DILL, D.B., HALL, F.G. and EDWARDS, H.T. (1938): Changes in composition of sweat during acclimation to heat. Amer. J. Physiol. 123: 412–419.
DILL, D.B., HORVATH, S.M., BEAUMONT, W.V., GEHLSEN, G. and BURRUS, K. (1967): Sweat electrolytes in desert walks. J. appl. Physiol., 23: 746–751.
HORI, S., INOUYE, A. and IHZUKA, H. (1974): Indices and sweating patterns for the assessment of heat tolerance. Jap. J. Physiol., 24: 263–275.
HORI, S., INOUYE, A., IHZUKA, H. and YAMADA, T. (1974): Study on seasonal variations of heat tolerance in young Japanese males and effects of physical training thereon. Jap. J. Physiol., 24: 463–474.
INOUYE, A., HORI, S. and IHZUKA, H. (1972): Heat tolerance index based on Ohara's sweating test. Proc. US-Japan Cooperative Research on Human Adaptabilities.
KUNO, Y. (1934): The Physiology of Human Perspiration. Churchill, London.
KUNO, Y. (1956): Human Perspiration. Charles C. Thomas, Springfield.
LADELL, W.S.S. (1951): Assessment of group acclimatization of women to heat. J. appl. Physiol., 18: 383–386.
OHARA, K. (1966): Chloride concentration in sweat; Its individual, regional, seasonal and some other variations, and interrelations between them. Jap. J. Physiol., 16: 274–290.
OHARA, K. (1967): Heat tolerance and sweating pattern. Comparative Methodology for Heat Tolerance Testing: A Comperative International Study US Dept. of HEW, Public Health Service, National Center for Urban and Indust. Health, Cincinnati, Ohio, 187–202.
OHARA, K. (1968): Heat tolerance and sweating type. Nagoya Med. J., 14: 133–144.
WILLIAMS, C.G., WYNDHAM, C.H. and MORRISON, J.F. (1967): Rate of loss of acclimatization in summer and winter. J. appl. Physiol., 22: 21–26.
WYNDHAM, C.H. (1967): Effect of acclimatization on the sweat rate / rectal temperature relationship. J. appl. Physiol., 22: 27–30.
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Hori, S., Nakamura, M., Sugawara, K. et al. A comparative study on sweating pattern and heat tolerance. A field study on residents of Okinawa in summer. Int J Biometeorol 19, 184–193 (1975). https://doi.org/10.1007/BF01460017
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DOI: https://doi.org/10.1007/BF01460017