Yoon, S., & Pascoe, D. D. (2004). Efficacy of a cooled vest on thermoregulation during cycling exercise in a hot and humid environment. Medicine and Science in Sports and Exercise, 36(5), Supplement abstract 2133.

This study investigated the effects of a water cooled vest and wind on thermoregulation during exercise in a hot and humid environment. Adult males (N = 8) exercised on a cycle ergometer at a 150 watt workload for 40 minutes in a heat chamber (33C, 60% relative humidity). During wind trials, a fan maintained a 6 m/s wind speed. The vest (Hydroweave) used thermal conduction of cooled water soaked into the inner layer to maintain a cool temperature. Each S performed four trials; no vest/no wind, vest/no wind, no vest/wind, and vest/wind. Heart rate, rectal core temperature, skin temperatures (chest, shin, thigh, and arm), and environmental condition were measured every five minutes. Expired gases were collected at pre- and post- trial to calculate heat production and heat loss.

Wind or wearing a vest demonstrated significantly lower heart rate, core temperature, and skin temperature. The combined influence of vest/wind was significantly greater than vest/no wind and no vest/wind. The amounts of evaporative and radiant heat losses were not changed by either vest or wind. The amounts of convective heat losses were greater in the no vest/wind and vest/wind trials compared to the no vest/no wind and vest/no wind trials due to the wind effect.

Implication. The use of a cooled vest and wind can decrease thermal load. The additive influence of wind and vest produced the best thermal relief.

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