I'm a fairly athletic guy (collegiate baseball player and former PGA Professional).....and I'm not surprised at your situation. I've also had a shoulder surgery....and I started out with the poundage on my 70 lb bow set @ 58lbs. It's simply an athletic/strength-requiring movement that I've never been introduced to.

It took me a couple of months before 58 lbs felt "easy". I then went to 62 lbs....and that's plenty, for now (maybe always???). I've also noticedthe difference when it's really cold out.I'm gonna take others advice and draw my bow more often, on stand.

Jeff