Please choose the correct ending to complete the given sentence: Uncategorized: [header] How to do pull ups for beginners [title] Do flexed arm hangs. [step] To build muscles in your shoulders and arms, start with flexed arm hangs. To do flexed arm hangs, place a box near the pull up bar that puts your chin just over the bar.

Ending1: Then put your arm through the box, and allow your thumb and index finger to rest on top of the weight. Carefully transfer the weight to your free arm. Ending2: Place the box to your right side so your feet are flat on the ground. Then lean forward over the bar so your face is towards the bar. Ending3: Release the box and lower your arms down so they are horizontally perpendicular to the bar. Use your non-dominant hand to support your lower back, offering a firm grip. Ending4: Place your hands on the bar with your palms facing you. Lift yourself upward and hold yourself slightly over the bar.

Answer format: ending1/ending2/ending3/ending4