Primary Muscle Group: Arms
Attach a handle to the floor-level cable and pull. Now grasp the handle with an underhand grip, hands about shoulder width apart. Keeping your elbows fixed at your sides, extend your arms out and down until your biceps are fully stretched. Curl the handle upward, not letting your elbows move, to a position just under your chin. Contract your biceps as hard as possible on the top, then lower the handle slowly back down until your arms are fully extended.