HOW: Grab onto a hammer with one hand. Keep that elbow to your side and bend your arm up to create a 90 degree angle. From here, grip the hammer with your palm facing in and thumb up. Allow the hammer to go forward, rotating your wrist downward. Pull the hammer back up without moving your shoulder. FEEL: You should feel the muscles in your forearm working. COMPENSATION: Don’t allow your arm or shoulder to move, only allow motion in the wrist. Exercise Library