One of the best exercises for shoulder pain and weakness is to allow the arm to swing in small circles. Put the opposite arm on a table or a secure surface and bend over from the waist, allowing the injured arm to hang down. Make small clockwise circles for about 30 seconds and then change directions and make small counterclockwise circles for the same time frame. Take a 30-second break and then repeat the exercise.
Posterior Joint Stretch
Take your injured arm and put it across your body at shoulder height. With your non-injured arm, grab the point of the elbow on the injured arm and pull it toward you. It may look to an outsider that you are choking yourself, but you are actually relieving stress and pressure in your shoulder. Do this stretch for 30 seconds, take a 15-second break and then do this stretch again.
External Rotation Stretch
Stand next to a wall with your injured arm. Bend your elbow at a 90-degree angle and put your hand on the wall. Rotate the trunk of your body away the wall very slowly until you feel a slight pressure in your shoulder. Stop when you feel the pressure and return to your original position. Do this 10 times, take a 30-second break and then repeat the set.
Take a towel and hold it behind your head and back. Your non-injured arm should be behind your back holding the bottom of the towel. Take your injured arm and hold the top of the towel at head level. Pull with your injured arm until you feel slight pressure on your shoulder. Do this for 30 seconds at a time, take a short break and then repeat the set.
Twist with Exercise Ball
Do this exercise with a partner. Place your backs against each other. Hold an exercise ball in your arms in front of you. Twist to your right with the ball and your partner will twist to his left. Hand the ball off to him. Then twist to your left as he twists to his right and accept the exercise ball from him. Do this slowly for two minutes. Take a 30-second break and then repeat the set.