Exercise can slow the ticking of the biological clock.

“And one of the reasons we believe that is that you can measure biological age now in people. I could take one of your cells, Matt, back to my lab. Well, actually I have to take a chunk of your cells or cheek swab, and we can measure the rate of your aging. It's called the Horvath clock or DNA methylation clock. And when you look at people that have lived a healthy lifestyle, say they've been exercising for the last 30 years. they are much younger epigenetically, according to this clock, than somebody who hasn't.”