Attach a pair of resistance bands to a door anchor and place the door anchor at the top of a door. Attach the workout bar to the other ends of the resistance bands. Stand facing away from the door and position both hands under the workout bar. Keep the bar behind your neck. Take one step forward and lean away from the door until resistance is felt.
Extend elbows until arms are straight. Return and repeat.
Let resistance pull arm back to maintain degree of shoulder flexion, dependent upon flexibility.