Specific timed exercise bouts can shift your body clock

by Shirley Archer, JD, MA on Oct 15, 2019
Fitness Journal, Volume 16, Issue 11
 
Maybe you’re familiar with using bright-light exposure to shift your body clock so you can overcome jet lag more quickly. But what about exercising to achieve the same goal? Researchers at Arizona State University and the University of California, San Diego, found that exercising at 7 a.m. or between 1 p.m. and 4 p.m. was effective for advancing the body clock, whereas training between 7 p.m. and 10 p.m. worked to delay the clock. “Delays or advances would be desired . . . for adjustment to westward or eastward air travel, respectively,” the study noted.

Lead author Shawn Youngstedt, PhD, professor in the Colleges of Nursing and Health Innovation and Health Solutions, Arizona State University, said in a press release, “Exercise has been known to cause changes to our body clock. We were able to clearly show in this study when exercise delays the body clock and when it advances it. This is the first study to compare exercise’s effects on the body clock and could open up the possibility of using exercise to help counter the negative effects of jet lag and shift work.”
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The study appeared in The Journal of Physiology (2019; 597 [8], 2253–68).

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