Part of the shoulder-forward pattern is the internal rotation of the shoulder joint itself.
The quickest and simplest way to externally rotate your shoulder is to stand up and:
- flex your arms to a 90-degree angle with your hands facing each other,
- rotate your arms so that your palms face forward,
- pinching your shoulder blades together at the end of the motion.
Simply repeating this motion will begin to undo the internal-rotation pattern, but adding resistance to the exercise will strengthen the external shoulder rotators even more.
This video shows how to strengthen your external shoulder rotators lying on your side and using a light dumbbell. The rolled-up towel between the model’s forearm and torso positions the arm to specifically target the external shoulder rotators on the back of the scapula.
This video shows how to strengthen the external shoulder rotators using a Thera-Band.