Effects of Burn Injuries on Thermoregulatory and Cardiovascular Responses in Soldiers: Implications for the Standards of Medical Fitness

The aim of this study was to investigate whether the absolute effective body surface area BSA or the BSA burned best predicts the core temperature response to exercise in the heat. Sixteen healthy non-burned individuals 8 large LG and 8 small SM were recruited. On separate occasions, subjects cycled at 100 W for 1 h in a 39C, 20 relative humidity environment with a simulated burn injury of 0 or 40 total BSA. A simulated 40 burn injury reduced the effective BSA to1.350.05 m2 and 1.010.07 m2 in LG and SM groups, respectively. Greater elevations in core temperature were observed in SM, irrespective of condition. For both groups, the elevation in core temperature was exacerbated by the 40 simulated burnP0.01, yet the magnitude of the increase in core temperature from 0 to 40 simulated burn was not different between groups P0.37. Despite the same 40BSA burned, smaller individuals showed an 0.75 C greater elevation in core temperature during exercise. In exercise-based rehabilitation or physically demanding occupational settings, activities performed at the same absolute intensity will place burn survivors of smaller body size, but with the same BSA burned, at greater risk for hyperthermia.