A lot of guys mentioned shoulder problems, torn rotator cuff, etc. I have had significant shoulder pain in my bow arm.
I saw a surgeon who thought I should try injections first. i did that and got relief that lasted 8 or 9 months as I recall. I did that about three times and then talked with a PT person who designed some exercises to build up the muscles around the shoulder.
That has worked great. When I started the exercises, it hurt just trying to get my jacket on. Now I am using stretch bands and that has worked very well for me.
As I posted earlier, 51, 52 lb bows are no problem for this 72 year old.