FOREHEAD SKIN TEMPERATURE AND THERMAL SENSATION DURING EXERCISE IN COOL AND THERMONEUTRAL ENVIRONMENTS

Background: The influence of forehead and mean skin temperature on thermal sensation during exercise in hot, cool, and thermoneutral environments is unclear. Hypothesis: We hypothesized that forehead temperature, in contrast to other skin sites, would contribute significantly to thermal sensation during exercise in hot, cool, and thermoneutral environments. Method: Volunteer males (N = 14) performed 30 min of constant load exercise on a cycle ergometer during which thermal sensation, skin and rectal temperatures, and heart rate were collected. Each subject participated in a control (24 degrees C), hot (40 degrees C), and cool (8 degrees C) condition. Results: Significantly higher mean skin temperatures occurred during exercise in the hot condition ((M) under bar = 37.22 +/- 0.20 degrees C) compared to exercise in the neutral ((M) under bar = 33.34 +/- 0.51 degrees C) and cool conditions ((M) under bar = 27.92 +/- 0.22 degrees C). Forehead skin temperature in the neutral and cool conditions was significantly greater than forearm, hand, thigh, and calf skin temperatures (p < 0.05). In the hot condition, forehead temperature was significantly greater than back, chest, upper arm, and hand skin temperatures (p < 0.05). in contrast to the neutral and hot conditions, forehead skin temperature was significantly associated with thermal sensation during exercise in the cool condition (r consistently >0.67). Conclusions: We conclude that forehead skin temperature, in contrast to other skin sites, contributed significantly to thermal sensation during exercise in the cool.