As I approached 80 I started to get the same kind of aches and pains OP describes. Over the previous year I had started doing more walking and exercises. Long story short, some online research showed that some of the "old school" exercises I was doing, such as stretching down to touch toes, did more harm than good. Also, that at my age, most exercises should be done slowly with fewer reps. I'd suggest OP do some concentrated research as to which exercises are best for his situation. Not that I no longer have aches & pains...get rid of one, find another. Part of the adventure of ageing