Exercising at Night is Better for You

When is the best time to work out?

Experts have been debating this question for years but new data suggests that exercising at night may be better for you than squeezing in a morning run.

In two new studies of mice, researchers from the Weizmann Institute of Science and the University of California, Irvine, noted improved performance in rodents exercising at night.

Until now experts have considered the timing of food intake as the most important factor when it comes to enhanced athletic ability but, as Paolo Sassone-Corsi of the University of California noted, the topic of when is the best time to exercise has been a relatively unexplored topic.

Both teams analyzed data collected from tests conducted of mice running on treadmills.

Researchers from the Weizmann Institute of Science examined the performance of mice exercising at different intensities at different times of the day and noted a 50 percent increase in overall performance at night.

Meanwhile, the California team took a different approach by observing changes in the metabolism of mice occurring during exercise at different times of the day. Both teams arrived at the same findings: Evening appeared to be the best time to exercise, for the mice at least, and this boils down to the circadian clock.

"Circadian rhythms dominate everything we do," said Sassone-Corsi "Previous studies from our lab have suggested that at least 50% of our metabolism is circadian, and 50% of the metabolites in our body oscillate based on the circadian cycle. It makes sense that exercise would be one of the things that's impacted."

Sassone-Corsi added that the test results "clearly indicate that time-of-day is a critical factor to amplify the beneficial impact of exercise on both metabolic pathways within skeletal muscle and systemic energy homeostasis."

However, both teams of researchers pointed out that although circadian clocks have been conserved throughout evolution, it is not as simple to translate these results to humans. Lifestyle may come into play.

"You may be a morning person, or you may be a night person, and those things have to be taken into account," Sassone-Corsi says.