Kondo, N., Yanagimoto, S., Kuwahara, T., Zhang, Y., Koga, S., & Inoue, Y. (2004). Heat loss responses at the onset of dynamic exercise in endurance-trained men under mildly heated conditions. Medicine and Science in Sports and Exercise, 36(5), Supplement abstract 2138.

This study investigated the heat loss responses at the onset of dynamic exercise in endurance-trained men under mildly heated conditions. Trained (N = 8) and untrained (N = 9) men performed a cycle exercise in semi-supine position at 30, 50 and 70% VO2max for 60 seconds with at least a 10-minute interval in mildly heated conditions. Exercises were conducted after each S was exposed at to an environment of 35°C and 50% relative humidity.

Esophageal and mean skin temperatures were steady in both the groups throughout the experiments. The heart rate, rating of perceived exertion, mean arterial pressure, and sweat rate from the non-glabrous skin (chest, forearm and thigh) increased linearly with a rise in exercise intensity in both groups. Sweat rate from the glabrous skin (palm) showed intensity-dependent responses only in the trained group. The mean sweat rate of non-glabrous skin was significantly higher in the trained group than the untrained group.

Implication. Endurance training enhances sweat rate responses without marked change in body temperatures at the onset of dynamic exercise. Training induces more increase in sweat rate in both the of non-glabrous and glabrous skin sites.

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