HOW: Get set up sitting upright with your arm held out in front of you with your elbow straight. While maintaining elbow position and holding a long weighted object such as a bat, perform pronation and supination. See the video for other tips and instructions.
FEEL: You should feel the muscles on top of your forearm working as well as other muscles in your forearm and hand to help with gripping the object. You may feel tension on the outside of your elbow as well.
COMPENSATION: Perform slowly, do not lose elbow position, try to strictly rotate your arm on a swivel.