Circadian rhythm is a natural, internal mechanism that regulates human physiology and behaviour to different phases of the day. Meanwhile, nearly all cells in the body have an internal biological circadian clock that is synchronized by external cues. A variety of factors including hormones, temperature, food-intake, and exercise can act on tissue-specific peripheral clocks to alter the expression of genes that influence metabolism. A group of researchers from Sweden and Denmark hypothesized that timing of exercise and feeding status can influence metabolism in adipose tissue and carried out a trial in mouse model. The adipose tissue of healthy mice was examined after a session of high-intensity exercise performed at two points of the daily cycle (late morning and late evening). Results suggested there is a time-of-day-specific effect of metabolic response to exercise, which is partially independent of feeding status and circulating levels of glucocorticoid and adrenaline. This sensitivity is found most pronounced during the late morning session. Further investigation in its implication in improving energy homeostasis in obesity or type 2 diabetes models is required.

Reference:

Pendergrast et al. Proc Natl Acad Sci U S A. 2023;120(8):e2218510120. doi:10.1073/PNAS.2218510120/SUPPL_FILE/PNAS.2218510120.SAPP.PDF