STARTING POSITION:
Select the appropriate resistance on the weight stack. Kneel on a assisted pull-up machine and grab the handles using a prone grip wider than shoulder width apart. Contract your pelvic floor and core while keeping your chest up.
MOVEMENT:
Retract your shoulder blades rising your chest up. Contracting your back muscles, pull your upper body up until your chin is above the bar while you exhale. Return to the starting position in a smooth movement while you inhale.
TIPS: The exercise key is quality over quantity. The trick is to perform the exercise using proper form. Make sure your shoulders are far from the ears when you perform the ascent to the bar.