Shiro Oda1, Kazuki Shirakawa. 1. Department of Sport Education, School of Lifelong Sport, Hokusho University, 23 Bunkyodai, Ebetsu, Hokkaido, 069-8511, Japan, os@hokusho-u.ac.jp.
Abstract
PURPOSE: Many studies have failed to show that pre-sleep exercise has a negative effect on sleep onset. However, since only a moderate level of physiological excitement was observed at bedtime in these studies, it remains unclear whether a larger magnitude of physiologic excitement present at bedtime would disrupt sleep onset. This study compared the effects of pre-sleep exercise, which led to different levels of physiologic excitement at bedtime (moderate and heavy), on sleep onset. METHODS: Twelve active young men underwent non-exercise, moderate-intensity exercise, and high-intensity exercise conditions. The subjects maintained a sedentary condition on a reclining seat throughout the day. On the non-exercise day, the subjects remained seated at rest until going to bed. On the moderate- and high-intensity exercise days, the subject exercised for 40 min (21:20-22:00) at 60 and 80% heart rate reserve, respectively. Sleep polysomnography, core body and skin temperatures, heart rate (HR), and heart rate variability (HRV) were recorded. RESULTS: We observed a delay in sleep onset (+14.0 min, P < 0.05), a marked physiological excitement at bedtime as reflected by an increased HR (+25.7 bpm, P < 0.01), and a lower high-frequency power of HRV (-590 ms(2), P < 0.01) only on the high-intensity exercise day. CONCLUSIONS: These results indicate that pre-sleep vigorous exercise, which causes a large physiologic excitement at bedtime, might disrupt the onset of sleep.
PURPOSE: Many studies have failed to show that pre-sleep exercise has a negative effect on sleep onset. However, since only a moderate level of physiological excitement was observed at bedtime in these studies, it remains unclear whether a larger magnitude of physiologic excitement present at bedtime would disrupt sleep onset. This study compared the effects of pre-sleep exercise, which led to different levels of physiologic excitement at bedtime (moderate and heavy), on sleep onset. METHODS: Twelve active young men underwent non-exercise, moderate-intensity exercise, and high-intensity exercise conditions. The subjects maintained a sedentary condition on a reclining seat throughout the day. On the non-exercise day, the subjects remained seated at rest until going to bed. On the moderate- and high-intensity exercise days, the subject exercised for 40 min (21:20-22:00) at 60 and 80% heart rate reserve, respectively. Sleep polysomnography, core body and skin temperatures, heart rate (HR), and heart rate variability (HRV) were recorded. RESULTS: We observed a delay in sleep onset (+14.0 min, P < 0.05), a marked physiological excitement at bedtime as reflected by an increased HR (+25.7 bpm, P < 0.01), and a lower high-frequency power of HRV (-590 ms(2), P < 0.01) only on the high-intensity exercise day. CONCLUSIONS: These results indicate that pre-sleep vigorous exercise, which causes a large physiologic excitement at bedtime, might disrupt the onset of sleep.
Authors: Hugh H K Fullagar; Sabrina Skorski; Rob Duffield; Daniel Hammes; Aaron J Coutts; Tim Meyer Journal: Sports Med Date: 2015-02 Impact factor: 11.136