The Measurement Of Whole Body And Regional Upper Body Sweat Rates

There were many difficulties in determinating human whole body sweat rates in practice by previous methods. A new method which was called clothing weight gain was put forward for measuring the amount of sweat produced by human body. With this method the whole body sweat rates were measured after 8 subjects ran on a treadmill for 15 min at speeds of 0.90m/s (2mi/h), 1.78m/s (4mi/h),2.68m/s (6mi/h) and in the ambient temperature of 20℃,25℃,28℃respectively. By carrying out paired-samples t test, the measurement results of sweat rates were analyzed. It was found that both ambient temperature and activity intensity had significant effects on sweat rate per unit area. When the ambient temperature was 20℃,25℃,28℃and activity intensity was 0.90m/s,1.78m/s,2.68m/s respectively, the sweat rate per unit area was in the range of 1.605-681.100 g/(h-m2). Also, it demonstrated that clothing weight gain was an effective method for determining human whole body sweat rates.At mean time,10 cardiopulmonary function indexes were surveyed during the determination of whole body sweat rates. By carrying out Pearson correlation analysis, it was found that there was no correlation between respiratory exchange ratio and sweat rate per unit area, O2 equivalent ventilation and sweat rate per unit area, CO2 equivalent ventilation and sweat rate per unit area. In contrast, all of the other 7 cardiopulmonary function indexes presented a notable positive correlation with sweat rate per unit area. At last, they were sorted according to the value of correlations and the order was O? uptake>VE minute ventilation>CO2 emissions>relative O2 uptake> metabolic equivalent>tidal volume>respiratory rate. It suggested that cardiopulmonary function indexes could be a general description of comprehensive degree of heat and activity intensity. Meanwhile, cardiopulmonary function indexes could forecast sweat rate per unit area.In addition, with filtering paper method 10 regional upper body sweat rates of one male subject were measured after he ran on a treadmill for 15 min at speeds of 0.90m/s,1.78m/s, 2.68m/s and in the ambient temperature of 20℃,25℃,28℃respectively. By carrying out paired-samples t test, it was concluded that when confidence was 90%,10 upper body sites could be divided into 4 groups by comparing sweat rate per unit area and the significant difference between them. The order was mid front>left lower back and left mid back>top front, left scapula and lower front>left shoulder, upper arm, upper central back and mid central back.All the paired-samples t test results implied that both ambient temperature and activity intensity had significant effects on regional upper body sweat rate per unit area except for the paired-samples of 20℃,0.90m/s and 20℃,1.78m/s. When the ambient temperature was 20℃, 25℃,28℃and activity intensity was 0.90m/s,1.78m/s,2.68m/s respectively, the regional upper body sweat rate per unit area of the male subject was in the range of 2.0-1418.4 g/(h·m2).The measurement of whole body and regional upper body sweat rates provided some basic physiological data for the research of heat-moisture comfort of gannent under sweating condition and improved people's knowledge of regional upper body sweat differences. Also, it could be used in sportswear design, fabrics selection, thermo-physiological modeling and thermal manikin design.