Instructions
Set the bar to your waist height.
Lie on your back under the bar.
Reach up and grip the bar with an overhand grip with both hands.
Keeping your body straight, pull yourself up towards the bar by pulling your elbows as far back as you can and trying to touch the bar with your chest.
Hold and squeeze your arm and back muscles.
Lower yourself back to the start position in a controlled motion.
Repeat.