Exercise-induced increase in core temperature does not disrupt a behavioral measure of sleep

On separate nights 90 to 30 min before typical bedtime, eight physically active men completed three conditions: seated rest, low-intensity and moderate-intensity cycle exercise. Low-and moderate-intensity exercise had no significant effect on sleep onset latency, the number of awakenings, total sleep time or sleep efficiency as measured by the Sleep Assessment Device. Mean core body temperature was higher during sleep after moderate intensity (36.80 +/- 0.02 degrees C) exercise compared to both the low-intensity exercise (36.67 +/- 0.02 degrees C) and rest (36.51 +/- 0.02 degrees C) conditions. It is concluded that a l-h bout of moderate-intensity exercise performed shortly before bed elevates core body temperature before and during sleep; however, this elevated temperature does not disrupt behavioral measures of sleep obtained in the home environment in physically active male college students who were somewhat sleep deprived. (C) 1998 Elsevier Science Inc.