I have asked a similiar question in the general discussions forum, if you want to have a look. I'm fairly sure my shoulder and arm pains come from a poor swing that hits the ground too hard and thus causing impact stress. I found (I'm at golf as long as you) that when I started the game that after the first few rounds I was very "stiff" and thus sore. This was to be expected because the muscles were so unused to being used, but after a few rounds the stiffness would not occure (the muscles adapted). Whereas now I'm actually sore (from hitting the solid mats at the driving range). Maybe you are having a similar problem as myself....