It's so wild that in your 50s you can be more fit and in better health than you were in your 30s. No one ever told me this. My sedentary family bitched and moaned about how they were getting old and their bodies were falling apart every day. I'm so glad I discovered that exercise works in my early 40s. I hear you about injury though. When I get injured now it takes ages to recover. Something that would have gone away in 2 days in my 20s, can take weeks to heal. We're not immortal, but there's so much we can do.

I got a bad of case of tennis elbow recently from over-exerting during a light set of pushups!

The joint stuff you have to think about, where it was barely a consideration when I was younger.