In this video, you are shown how to alternate hammer curls, while standing up, with dumbells. They instruct you to stand up, with your legs slightly bent, so you down overload your spine. Having your dumbells at your side, keep your back straight. Next you are advised to flex your forearm, keeping your elbow as still as possible, and lower your forearm back to the starting position, and repeat with the other arm, and remembering to breathe. They reveal some common mistakes with this workout, including, arching your back to facilitate the start of action, and moving your elbow forward during flexion.