Simply Put

There is no real mystery here.  When I was a kid I never stopped moving.  When I become a somewhat serious athlete it was 2 1/2 to 3 hours of practice per day, lifting, walking or riding the bike home, go for a run every day.  In college that only increased.

Then through my 20s there was club lacrosse, summer leagues, pick-up basketball and the habitual daily run.

30s was the same thing, with much more travel, but no desserts when traveling, no red meat, no cheese, and what I liked to call "running tours."  I would literally get to know the places I was, from DC to Brussels, to Bern, to Steamboat, by running different loops around town.  If that wasn't possible there was always the runs up and down the hallways and stairways in hotels.

40s was coaching and running, and especially at Chico State it was a run every morning early and then off to the office, plus lifting 6 nights a week.

Fast forward to now, wrecked my knee, stopped running, starting eating fast food after late practices and so my metabolism is essentially stopped, relative to what it was, and my exercise is zero.

All one can do is keep trying.

It is a choice.