Military personnel often must work in hot environments, increasing the risk of hyperthermia. Our purpose was to evaluate a new rapid thermal exchange device (RTX) in slowing the development of hyperthermia and associated symptoms to 3 other conditions [hand immersed in water bath (WB), water-perfused vest (VEST), and a no- cooling condition (NC)] in subjects exercising in a hot environment (42C, 30% rh) wearing summer fatigues, a backpack and body ...