Physiological Responses of Men to Wet Tropical Environmental Conditions (Operation Swamp Fox II)

摘要

Army personnel under heat stress were observed while walking up and down a 12.5 degree slope and while confined (as a squad) for up to six hours in an armored personnel carrier at an unforested tropical site. Measurements of bodily temperatures, pulse rates, and sweat production were used as indices of heat strain in the men. Subjects walking in the sun, unloaded, did not suffer excessive heat strain under midday tropical conditions. About two-thirds of the sweat produced was evaporated for body cooling. Data on confined men showed there was little risk they would become heat casualties when exposed to effective temperatures up to 33.3C. (92.0F.) for as long as four hours. The men showed physiological adjustments to changes in environmental stress in less than 10 minutes. (Author)