When Is The Best Time Of The Day To Exercise?

The health and fitness community has always been busy trying out the latest exercise and wellness trends. No one really took the time to analyze if working out at a certain period of the day would yield faster and better outcomes. But a team of scientists changed that.

In a study recently published in the Proceedings of the National Academy of Sciences, researchers determined the best time of the day to exercise to burn more fat. The discovery could change how most people plan their daily routines to fit their regular dose of exercise.

Working out at different times of the day affects the body in different ways due to the biological processes that rely on circadian rhythms. The team found that exercising in the morning resulted in better outcomes since this is the perfect time of the day to boost fat metabolism.

“Nearly all cells in the body have an internal biological circadian clock that is synchronized by external cues. This machinery forms a transcription-translation feedback loop that anticipates and adapts organismal physiology throughout the 24-h day-night cycle,” the scientists explained.

They continued, “We tested the hypothesis that timing of energetic stressors that affect glucose and energy homeostasis, namely exercise and feeding status, can differentially influence metabolism in adipose tissue.”

To test their hypothesis, the researchers from Karolinska Institutet in Sweden and the University of Copenhagen in Denmark studied two mice groups. One group performed high-intensity exercise in the morning. The other group performed the same routine in the evening. The team then analyzed the different biological processes and markers for fat metabolism in both groups.

“We found that acute exercise elicits a timing-specific effect on adipose tissue, which is independent of feeding status. Adipose tissue sensitivity to exercise is timing-dependent and modulated in a cell-autonomous fashion, as evidenced by enhanced transcription of metabolic genes in early active phase. Thus, exercise timing may fine-tune adipose metabolism to improve energy homeostasis in cardiometabolic disease,” the team wrote.

Karolina Institutet’s Juleen R. Zierath, a professor in the department of molecular medicine and surgery and the department of physiology and pharmacology, noted that their findings could be beneficial for overweight people who may be struggling to shed pounds, as per the New York Post.

“Our results suggest that late morning exercise could be more effective than late evening exercise in terms of boosting the metabolism and the burning of fat, and if this is the case, they could prove of value to people who are overweight,” Zierath said, as quoted by the outlet.

Meanwhile, previous research from the Warren Alpert Medical School at Brown University found that working out at the same time of the day regularly resulted in successful weight loss compared to working out at random times of the day.

The 2019 study claimed that regardless of the specific time of day of routine exercise, consistency in timing was paramount in ensuring successful weight loss and weight maintenance.