Improved sleep may improve exercise duration

(HealthDay)—The length of an individual's sleep appears to influence their participation level in exercise the next day, according to a small study published in the August issue of the Journal of Clinical Sleep Medicine.

Kelly Glazer Baron, Ph.D., M.P.H., from Feinberg School of Medicine at Northwestern University in Chicago, and colleagues studied self-reported data from 11 women (mean age, 61.27 years) with insomnia who engaged in 30 minutes of aerobic exercise three times a week. Sleep quality was assessed at baseline and at 16 weeks. Additionally, sleep and exercise logs and wrist activity were collected continuously.

The researchers found that total sleep time (TST), sleep efficiency, and self-reported global sleep quality improved significantly from baseline to 16 weeks. There was a significant, negative correlation between baseline ratings of sleepiness and exercise session duration. There was no association between daily exercise and subjective or objective sleep variables during the corresponding night. Following nights with longer sleep onset latency, participants had significantly shorter exercise duration. For participants who had shorter TST at baseline, the relationship between shorter TST and shorter next day exercise was stronger.

"Results suggest that sleep influences next day exercise rather than exercise influencing sleep," the authors write.

One author disclosed financial ties to the pharmaceutical and medical device industries.