Winter Trees at SunsetIt could all be about circadian rhythms, but what exactly are they? They are physical, mental and behavioral changes that follow a roughly 24-hour cycle,responding primarily to light and darkness in an organism’s environment. Circadian rhythms can influence sleep-wake cycles, hormone release, body temperature and other important bodily functions. They have been linked to sleep disorders, such as insomnia. Abnormal circadian rhythms have also been associated with obesity, diabetes, depression, bipolar disorder and seasonal affective disorder.

So what does this mean for exercise? In a study done on mice at the University of California’s Brain Research Institute, afternoon exercise seemed to have the best positive effect on these rhythms by resetting this “clock.” Researchers looked for the mice to produce a critical internal clock protein.

Those mice who exercised in the afternoon had more pronounced benefits than the other mice. The conclusion the researchers made, although not tested on humans, is that exercising in the afternoon would benefit us as well, especially if you suffer from insomnia, depression, and other problems caused by disrupted circadian rhythms.

However, remember some exercise is better than no exercise. Therefore, if afternoon workouts do not fit into your schedule, keep doing what you are doing.

Reynolds, Gretchen. “Why Afternoon May be the Best Time to Exercise.” NY Times, Dec. 2012.

Courtesy of Exercise ETC, Compiled by Laura Abbott, MS, LMT


*Valeo Personal Training offers a wide-range of hours to workout and we work to accommodate your schedule! 

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