Strength training is a great way to protect your muscles and tendons from repetitive strain. My biases is towards heavier weights with less reps but the most important factor is just doing the work. Whether you chose high loads and low reps or lower loads and higher reps, consistency will always get you results.
In this video I show three pulling exercises. I like to strengthen the shoulder through pushes, pulls, presses, and creative or dynamic ranges. If you do this work consistently in the off-season and a little during the season you will stay strong through all planes and keep you playing longer and stronger.