I'll give it a shot. Your rotator cuffs are a bunch of tendons that stabalize your shoulders. You probably use them while doing most exercises. Easily overtrained and easily injured. Proper form, intelligent workouts and warming up will save u months of rehabilition.
U use them when you do chest, shoulders, triceps, back, lightly with biceps, and legs...if you squat. If you want to know more about the rotator cuffs just do a search on the internet....huge topic.
rotator cuffs are 4 small muscles that act against gravity to hold the arm in the shoulder jont- stabilizers... as musulphreak said, rehab for them is slow...often overused or improper form (behind the neck x's, excessive overhead movements) or lack of warm-ups take you out of the gym for extended time w/ rotator injuries.... some people never recover to original strength... cortisol shots or surgery is common for rehab
To strengthen them and prevent injury use these two excercises.
1. Sit on the floor, side on, next to a bench and with your elbow on the bench, hold a light dumbell with your forarm sticking over the edge. Rotate the shoulder so that the dumbell comes to a vertical position, keeping the arm bent at 90 degrees throughout the movement. As I said, very light - 15-20 reps.
2. Opposite movement stood up using a high one armed pully (like on a cable crossover). Keep the arm out and again at 90 degrees and do an arm wrestling movement.
A couple of sets of each is enough to warm up and help strengthen the rotator cuff tendons. Just don't go too heavy.
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