Experimental study of thermo-physiological responses of exercising subjects in -10 ℃5 ℃ cold environments
CHEN Feiyu1, FU Ming2,3, SHEN Shifei1, LI Yayun2,3, GUO Xian2,3
1. Institute of Public Safety Research, Department of Engineering Physics, Tsinghua University, Beijing 100084, China; 2. Hefei Institute for Public Safety Research, Tsinghua University, Hefei 230601, China; 3. Anhui Province Key Laboratory of Human Safety, Hefei 230601, China
Abstract:Human thermo-physiological responses to cold environments need to be accurately known to assess human thermal safety and thermal comfort in cold environments. Existing studies have mainly concentrated on people at low exercise intensity, with little consideration of exercising people. Human subject experiments were conducted in a climate chamber to study the thermo-physiological responses and the factors influencing the responses of people exercising in cold environments. The thermo-physiological parameters, including the skin temperature, core temperature and thermal sensation, were measured from six young men for various ambient temperatures of 5, 0, -5 and -10℃ and two clothing with 2.57 and 1.34 clo. The results show that the mean skin temperature and the local skin temperature are linearly related to the ambient temperature with the slope decreasing with additional thermal clothing insulation. The rate of change of the core temperature is linearly related to the body's heat accumulation rate with the slope increasing with additional thermal insulation. Thermal sensation is affected by the ambient temperature and clothing at low and medium exercise intensities, but is not significantly affected at high intensities. The thermal sensation of the exercising people shows no correlation with physiological temperature. The results lead to suggestions to the choice of clothing for exercising people in cold environments. This research provides reference for assessing the thermal safety, thermal comfort, exercise capability and clothing needs for exercising people.
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