CONCLUSION
A low dose of HIIT is sufficient to reduce transcriptomic age in sedentary, middle‐aged adults. Other changes in gene expression were relatively modest in comparison with the transcriptomic age reduction effect size. These findings, along with modification to autophagic pathways, may indicate a particular HIIT specificity for age‐related biological pathway modulation. The key observations presented here, namely reduced transcriptomic age, indicate that exercise may potentially improve health and longevity by altering age‐related transcriptional processes.