From about 45-53 I did pretty hard training with a trainer and in classes 3-5 times per week. I was in good shape, no gut and could do a lot without getting the least bit winded. We did lots of burpees, squats, pushups, etc. My knees have been an issue for a long time so I quit all that after my first knee surgery in '17. First of all, SAVE YOUR JOINTS! Running and jumping and deep squats are not your friend. Modify, use bikes and less impactful cardio options as much as possible. Stretching, yoga, pilates are good to use once a week or more but stretch and warmup at each exercise session. Eat as good as you can, enjoy your life, just don't overindulge...to much.
As said before you are already doing more than most here so keep it up, you're doing fine!
