Exercise is crucial for human health. Beyond strengthening muscles and cardiorespiratory function, exercise can manipulate our body's gene switches, a process known as methylation.

Our genes are like a cookbook, containing recipes for all parts and functions of the body. Methylation, on the other hand, is like a bookmark in this cookbook. These chemical tags called methyl groups attach to DNA, marking which recipes (genes) should be read (expressed) and which should be skipped. When methylation patterns change, gene activity adjusts accordingly, thereby influencing our health.

Research shows that physical exercise such as running, swimming, or weightlifting can cause changes in our genome. For instance, in skeletal muscle, exercise can reduce methylation marks on certain genes such as PGC1α. PGC1α is essential for energy metabolism and mitochondrial biogenesis. When methylation at this site decreases, the gene becomes more active, enhancing muscle metabolic capacity.

Exercise also affects methylation in the brain and heart. In the brain, exercise can alter the methylation patterns of genes related to neuroplasticity and memory. For example, demethylation of the BDNF gene helps improve cognitive function and mood. In the heart, exercise-induced changes in methylation of specific genes may improve cardiac function.

References:

• Zheng, X., Liu, X., Guo, Y., Lv, Y., Lin, C., Wang, D., ... & Hu, X. (2025). Physical exercise and epigenetic modifications in skeletal muscle, brain, and heart. Epigenetics & Chromatin, 18(1), 12.
• Barres, R., Yan, J., Egan, B., Treebak, J. T., Rasmussen, M., Fritz, T., ... & Zierath, J. R. (2012). Acute exercise remodels promoter methylation in human skeletal muscle. Cell metabolism, 15(3), 405-411.