I was constantly running into shoulder problems as my lifts went up - then I started adding in the move... how to describe...
I hold a plate (light - 10lbs but started lighter) and then hold my elbow up so that it is parallel to the ground and my hand is up in the air - my forearm at a right angle to my upper arm.
then I lower the weight as far as I can forward and backward without pain.
I do 20 reps on each side.
also with cables, or rubber tubes there is another one where you do the same motion, but with your elbow at your side so that your forearm is the one that is now parallel to the ground and you are pivoting it so that your hand goes in front of you. I've seen people do this with free weights, but unless you are lying on your side on a bench, granvity doesn't play into it correctly.
does any of that make sense? way easier to show.
anyway - after doing those, no more shoulder probs (knock on wood).
my lifts went up, but I'm still a pussy and don't lift that much.