By Gretchen Reynolds, New York Times
Exercise may affect how and when we move, even when we aren’t exercising, according to a fascinating new study in mice. The findings suggest that, by influencing our built-in body clocks, exercise may help our bodies to recognize the optimal times we should be moving, and when we should be still.
Most of us have heard of circadian rhythms. Our heartbeats, hormones, hunger, alertness, digestion, fatigue and other bodily functions move through regular cycles on a schedule that is both predictable and syncopated, changing as circumstances demand.
But probably few of us realize that physical activity, both in people and most animals, likewise tends to follow a broad, circadian pattern.
Most obviously, we tend to sleep at night, hardly moving, and be active during the day.