For those of you farther down life's trail than I, what have you done to
maintain your edge? Any tips on staving off old man winter as long as
possible?

And for those of you who have hung it up, what made you do it? When did you
know it was time?

I'm 67 and developed heart disease 4 years ago (bypass in 2001). FAA
lets me fly as long as I can pass my treadmill test. I've done
aerobic exercise for 30 years (running, biking) and this made it easy
to recover from the surgery (back to work in 5 days) and continue
flying. Got my instrument rating last fall to help handle this
sometimes vile Great Lakes weather.