Morning and evening physical exercise differentially regulate the autonomic nervous system during nocturnal sleep in humans.
Effects of daily physical exercise in the morning or in the evening were examined on circadian rhythms in plasma melatonin and core body temperature of healthy young males who stayed in an experimental facility for 7 days under dim light conditions (<10 lux). Sleep polysomnogram (PSG) and heart rate variability (HRV) were also measured. Subjects performed 2-h intermittent physical exercise with a bicycle ergometer at ZT3 or at ZT10 for four consecutive days, where zeitgeber time 0 (ZT0) was the time of wake-up. The rising phase of plasma melatonin rhythm was delayed by 1.1 h without exercise. Phase-delay shifts of a similar extent were detected by morning and evening exercise. But the falling phase shifted only after evening exercise by 1.0 h. The sleep PSG did not change after morning exercise, while Stage 1+2 sleep significantly decreased by 13.0% without exercise, and RE sleep decreased by 10.5% after evening exercise. The nocturnal decline of rectal temperature was attenuated by evening exercise, but not by morning exercise. HRV during sleep changed differentially. Very low frequency (VLF) waves increased without exercise. VLF, low frequency (LF), and high frequency (HF) waves increased after morning exercise, whereas HR increased after evening exercise. Morning exercise eventually enhanced the parasympathetic activity, as indicated by HRV, while evening exercise activated the sympathetic activity, as indicated by increase in heart rate in the following nocturnal sleep. These findings indicated differential effects of morning and evening exercise on the circadian melatonin rhythm, PSG, and HRV.
Department of Physiology, Hokkaido University Graduate School of Medicine, Sapporo, Japan;
Yujiro
Y
Yamanaka
Research Center for Cooperative Projects, Hokkaido University Graduate School of Medicine, Sapporo, Japan;
Satoko
S
Hashimoto
Laboratory of Oral Chronobiology, Graduate School of Dentistry, Osaka University, Osaka, Japan;
Nana N
NN
Takasu
Department of Pediatrics, Asahikawa Medical University, Asahikawa, Japan; and.
Yusuke
Y
Tanahashi
Department of Physiology, Hokkaido University Graduate School of Medicine, Sapporo, Japan;
Shin-Ya
SY
Nishide
Department of Chronomedicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan kenhonma@med.hokudai.ac.jp.
Sato
S
Honma
Department of Chronomedicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
Ken-Ichi
K
Honma
D000222:Adaptation, Physiological / Q000502:physiology; D001341:Autonomic Nervous System / Q000502:physiology*; D001833:Body Temperature Regulation / Q000502:physiology; D002940:Circadian Rhythm / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology; D006706:Homeostasis / Q000502:physiology*; D006801:Humans; D008297:Male; D008550:Melatonin / Q000097:blood; D017286:Polysomnography; D012890:Sleep / Q000502:physiology*; D055815:Young Adult
D008550:Melatonin
autonomic nervous system; body temperature; heart rate variability; melatonin; physical exercise; sleep EEG