Exercise timing and circadian regulation of metabolism in type 2 diabetes

The circadian system regulates daily rhythms in metabolism and hormone secretion; however, in type 2 diabetes, disrupted clock gene oscillations in skeletal muscle impair metabolic regulation. Insulin resistance, mitochondrial dysfunction, and chronic inflammation contribute to this circadian misalignment. Exercise can restore circadian rhythms, yet optimal timing has only recently been explored. In individuals with type 2 diabetes, afternoon and evening exercise yield greater improvements in glycemic control and insulin sensitivity compared with morning exercise, with intensity appearing to influence these effects. Thus, appropriately timed exercise may help correct circadian disruption and glucose dysregulation in type 2 diabetes. Nonetheless, further research is needed to elucidate the underlying mechanisms of exercise timing effects and establish evidence-based recommendations for clinical practice.