Maintaining physical capabilities in the 'marginal decade' is controllable and important for longevity.

“I don't know if I'm going to live till I'm 85 or 90 or 80 or whatever I mean I don't I don't feel like I have as much control over that I think there are some elements of bad luck that factor into that what I feel like I have much more control over is when I'm in my marginal decade can I still go for a rock will I carry 80 lbs on said Rock no way but I might be able to carry 10 or 20 will I be able to swim half a mile in a pool yeah will I be able to swim it as fast as I can now no chance but I could still swim half a mile and get out of the pool under my own power”