HOW: Grab onto a hammer with one hand. Bend your elbow and have your forearm straight out in front of you. Hold the hammer straight up gripping the bottom of the handle with your knuckles facing inward. Rotate your forearm and the hammer to the side . Then, pull the hammer back to the starting position when your knuckles are facing up and repeat for the prescribed amount of reps. FEEL: You should feel your forearm muscles working. COMPENSATION: Keep your elbow bent and at your side while rotating your arm. Exercise Library