Significance
DISEASE
Starting and adhering to a new exercise program is difficult, a fact perhaps best illustrated by the current sedentary behavior rate in the United States. A recent Centers for Disease Control and Prevention (CDC) telephone survey estimates that more than 25% of Americans participate in no physical activity outside of work (CDC, High‐intensity interval training is a potential tool to help combat this trend given the decreased time commitment (Cobbold, Despite the modest gene expression findings generally, the prespecified hypothesis regarding HIIT‐induced transcriptomic age reversal was proven out by the analysis. Considering that each exercise participant completed a combined 276 min of exercise over 1 month, only 2 h of which was high‐intensity exercise, the effect of HIIT on biological age appears promising.This study further supports the notion that adding even a small amount of exercise can be beneficial, given that just 12 HIIT sessions were shown to significantly improve TA and TAaccel. To the authors' knowledge, this is the first trial to demonstrate the effects of a specific exercise protocol on a next‐generation measure of biological age. The results suggest that exercise may exert a focal effect on age‐related patterns of gene expression and that such effects could potentially contribute to the positive health and longevity effects associated with exercise.