Pin the pulley height on a cable to its highest setting and pin a suitable weight. Your feet are planted firmly and your core is tight as you take position in front of the cable rack. Take an overhand grip on the bar, just outside of shoulder-width. It is preferable to stand away from the rack slightly so that your straightened arms are extended up and out to give you more range of motion and therefore more benefit in the movement. This is the starting position.
Commence the movement by using your back to squeeze the bar through an arc movement - the arms move from in front of your body to the sides of your body whilst remaining straight. Do not use momentum to pull the bar. The torso should remain stationary.
When the bar just touches your upper thighs, squeeze for a second and then reverse the movement by extending the arms to the starting position, inhaling as you do.