One of the biggest mistakes I see with gym users and athletes who attempt to strengthen their rotator cuff is that they usually use weights which are too heavy.
This simply loads the deltoid which takes all the weight, and the rotator cuff muscles do not benefit. There becomes an imbalance between a very strong deltoid, and weak rotator cuff muscles. I see this in some of the top Olympic Weightlifters and Powerlifters that I treat, and it ultimately leads to injury.
When exercising the rotator cuff muscles the following suggestions will help you to maximize their potential while minimizing the damage:
• Choose your weight carefully. Because the rotator cuff muscles are so small, using an oversized weight can put undue strain on the deltoid. Ideally you should not use a weight heavier than 3 kg (6.6 lbs.).
• Do not start off with a heavier weight. Start light and gradually work with increasing weight.
• Keep the movement slow and controlled. Faster is not better.
• Keep your wrists neutral.
• Warm up before and after exercise to allow the muscles to function more efficiently.