Muscles trained: Upper back, biceps
Secure a bar 3-4 feet above the floor in a squat rack or cage. Lie under the bar and grab it with a shoulder-width, pronated grip. Hang at arm's length from the bar with your body in a straight line from your ankles to your shoulders. Keep your body rigid and pull your chest to the bar. Pause, then lower yourself back to the starting position. You can make this exercise more challenging by placing your feet on a bench instead of the floor.