Practice physical activity at the right time of day seems to be key when it comes to increasing fat metabolism, at least in mice, science has just discovered.
A new study from the Karolinska Institutet in Sweden and the University of Copenhagen in Denmark shows that mice that exercised in an early active phase, which corresponds to morning Exercise In Humans, they increased their metabolism more than mice that exercised at a time when they normally rest.
Physical activity at different times of the day can affect the body in different ways, since biological processes they depend on the circadian rhythms of cells.
To determine how the time of day you exercise affects fat burning, researchers from the Karolinska Institutet and the University of Copenhagen studied mouse adipose tissue after a high-intensity exercise session performed at two points in the daily cycle, an early active phase and an early rest phase (corresponding to a late-morning and late-afternoon session, respectively, in humans).
The researchers studied various markers of fat metabolism and analyzed which genes were active in adipose tissue after exercise.
The researchers found that physical activity in an early active phase increased the expression of genes involved in breakdown of adipose tissuethermogenesis (heat production) and mitochondria in adipose tissue, indicating a higher metabolic rate.
These effects were seen only in mice that exercised in the early active phase and were independent of food intake.
“Our results suggest that exercise at the end of the morning could be more effective than late-night exercise in terms of boosting metabolism and burning fat, and if this is the case, it could prove valuable for overweight people,” says Prof Juleen R. Zierathfrom the Department of Molecular Medicine and Surgery and from the Department of Physiology and Pharmacology of the Karolinska Institutet.
Mice and humans share many basic physiological functions, and mice are a well-established model for human physiology and metabolism. However, there are also important differences like the fact that mice are nocturnal.
“Timing appears to be important for energy balance in the body and for enhancing the health benefits of exercise, but more studies are needed to draw reliable conclusions about the relevance of our findings to humans,” says Zierath.