You should look into Berberine. Far more beneficial overall in the body effecting a wide range of systems than Metformin and actually outperforms Metformin in clinical studies in the one thing it's actually supposed to do well.
I'm 49 and as someone who is in good enough shape to compete in fitness shows for my age, I hear you on that...constantly fighting some sort of nagging injury or muscle strain or something that just doesn't feel right.
Sucks, but all you can do is delay the inevitable.
I have a pretty comprehensive supplement regimen and virtually all natural diet tho so that definitely helps.
I also do 5:2 fasting where I do what amounts to a 30-36 hour fast twice a week.
I'm in better shape than I was in my 20s or 30s but I sure don't feel better on a day to day basis 🤣