When I have a sore shoulder or elbow from shooting, I do push-ups every morning. My pains vanish as snow for the sun. Start slow, begin with only a few and work your way up with one more every time. If it is too difficult for you or when you are un-trained, start with sitting on your knees.
I do 25 now, without too many problems. Take a day rest beween, so one morning push-ups, next morning rest, next morning push- ups again.
It did miracles for me and it cost you only one minute per day!