The influence of temporary semi-supine and supine postures on temperature regulation in humans

Abstract The present study was conducted to explore the influence of slight postural differences on temperature regulation in humans. The subjects were exposed to a hot environment for 50 min in two different postures (semi-supine and supine). Core body temperature fell consistently in spite of the very high atmosphere temperature in both postural conditions. Tympanic temperature became significantly lower in supine than in semi-supine posture in contrast with the parallel drops of esophageal and rectal temperature. Our results suggest that the temporary horizontal supine position (1) lowers the thermoregulatory set-point, and (2) enhances selective brain cooling in hyperthermia.

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