73, and still able to push it, inspite of skeletal issues, wonderful!
Apparently, you're in good shape, otherwise. Probably good genetics. That's the real key.
Most, aren't as fortunate. On the one hand, I had good genes, I'm 71, but Lyme disease since my late twenties has counteracted my good genes, so a long list off health issues.
For me, riding 20 miles is an accomplishment. Am I able to fully enjoy it? No, but just sitting home on the couch is lousy, and depressive, time drags. Liver issues preclude a lot of anti-inflammatories, so it's a vicious cycle.
I down graded from a Suzuki gs 650 gl [ran good] to a low miles 78 Honda cm400 Automatic! I would have liked to try a trike, but way out of my price range. Therefore, I decided to build a sidecar for the little Honda, took me a couple of months of serious "tinkering" but I managed to produce what I feel is a decent, functional product. Performance, probably similar to a Ural rig [on the street] at a small fraction of the cost. Sorry, don't know how to post pix on this site or I would have done a build report.
Anyway, if I hear you zooming up behind me, I'll pull to the side and wave as you fly by, you lucky bastard.