耐寒性の生理的指標

概要

論文の詳細を見る
As a part of the International Biological Programme (IBP), 1964-1972, a project team was organized in Japan for studies of human adaptability. This JHA project was actually started in 1966 and continued seven years. The project team developed several methods for assessing and analyzing human tolerance to cold and heat. The author, who engaged in this project, will present an outline of the studies made on the methods for determining cold tolerance. Whole-body cold tolerance test: Six male students, clothed in 1.0clo, were exposed to 5℃ and 10℃ for 1hr (Fig.1). Increase of metabolism (M) was larger in 5℃ than in 10℃ and larger in winter than in summer. Decrease of the weighted averaged skin temperature (Ts, Table 1) was larger in 5℃ than in 10℃ but no seasonal difference was observed (Fig.2). Ratio of increase of metabolism to decrease of skin temperature, i.e., ΔM/ΔTs or ΔM%/ΔTs, showed positive correlation between 5℃- and 10℃-values and between winter- and summer-values (Fig.3). The ratio was higher in 5℃ and higher in winter (Fig.4). As the individual variation of the ratio was much larger in 10℃ than in 5℃, exposure temperature of 10℃ was thought to be more suitable to rank the persons in cold tolerance. Decrease of skin temperature at hand might be used in the place of ΔTs. In the next experiment, thirteen male and thirteen female students were used for 10℃ exposure (Fig.5). ΔM and ΔM% were larger in males than in females but ΔTs showed no sexual difference. Indices of ΔM/ΔTs and ΔM%/ΔTs were higher in males (Table 2 and Fig.6). Then it was concluded that the metabolic response to cold was enhanced in winter and that response to cold in men was rather metabolic while was rather insulative in women. Water immersion test: The critical temperature, i.e., the lowest ambient temperature at which the resting metabolism is maintained without any excess heat production, is also one of the criteria of cold tolerance. Water immersion test has the advantages to determine the critical temperature that the ambient temperature can be easily controlled and that the skin temperature may be fixed and known. Table 3 is the result obtained by Dr.Inoue. Here, the insulation index; I=(Tr-Tw)/rate of skin heat loss. It is shown that the response to cold is metabolic in winter and is insulative in summer. Peripheral cold tolerance test: In this method, middle finger with a thermister attached to nail bed is dipped into ice water for 30min and changes in skin temperature are observed. Dr.Tanaka used six male and six female students for the test. The result is shown in Fig.7 and seasonal difference of peripheral vasoconstriction is clear but here is alittle sexual difference. (Yoshimura, H.et.al.: JIBP-Synthesis, vol.3, 1975, Tokyo Univ.Press)
人間-生活環境系学会の論文
1977-08-30

耐寒性の生理的指標

スポンサーリンク

概要

著者

関連論文

スポンサーリンク