HOW: Lay on a swissball on at your chest level with your knees resting on the ground. Bring your elbows up at your side straight out from your shoulders, squeeze your shoulder blades, and let your forearms hang down. Keeping an “L” shape in your elbow, pretend there is a rod from your shoulder to your elbow and rotate your arm up and back down.
FEEL: You should feel you shoulder and upper back muscles working
COMPENSATION: Keep your elbows straight out from your shoulder, don’t drop them.