Does exercise influence the body’s internal clock? Few of us may be conscious of it, but our bodies, and in turn our health, are ruled by rhythms. “The heart, the liver, the brain — all are controlled by an endogenous circadian rhythm,” says Christopher Colwell, a professor of psychiatry at the University of California, Los Angeles’s Brain Research Institute, who led a series of new experiments on how exercise affects the body’s internal clock. The studies were conducted in mice, but the findings suggest that exercise does affect our circadian rhythms, and the effect may be most beneficial if the exercise is undertaken midday.


