Abstract

To onvestigate possible factors on fall in skin temperature during initial muscular work, ten healthy male volunteers conducted bicycle exercise at work loads of 50 to 150 watts in a climatic chamber of ambient temperature of 10, 20, 30 or 40 degrees C (relative humidity, 45 to 55). Skin temperatures at seven to eight points over the body surface were measured by thermography and thermocouple recording system. In hot conditions, sweat rates were significantly higher at 40 degrees C than at 30 degrees C, whereas the fall in skin temperature was almost equal in both conditions. Skin temperature distribution during exerciseof both 50 and 150 watts at 10 or 20 degrees C, the skin temperaturebegan to decline immediately at the onset of the exercise. Increased work intensities produced reduction in skin temperature. The present results suggest that the fall in skin temperature during the initial exercise was not due to increased evaporative cooling, but was the result of vasoconstriction probably caused by non-thermal factors. Verf.-Referat