HOW: The goal of this exercise is to use your opposite arm as much as possible to facilitate improving the desired motion. Hold onto a stick or something light that is long enough to hold in both hands. You will use an alternative grip meaning one palm up and one palm down. For example, if you’re focusing on the right shoulder, have the left palm down and right palm up. Using your left arm, drive your right arm out to the side and overhead into shoulder abduction as far as you feel comfortable with. Slowly lower down and repeat, as you perform more reps you may increase your range of motion.
FEEL: In this example, you should feel your left arm doing most of the work and your right arm going for a ride. You should feel your right arm moving into an overhead position similar to a jumping jack motion. You may feel a stretch around your right shoulder and shoulder blade.
COMPENSATION: Do not lean side-to-side or backwards with your upper body. Do not shrug your shoulder. Try to not let your elbow bend if possible.