Grasp cable stirrup. Sit on preacher bench placing back of arm on pad with palm up.
Raise stirrup upward toward shoulder of same arm. Lower stirrup until arm is fully extended. Repeat.
Seat should be adjusted to allow arm pit to rest near top of pad. Back of upper arm should remain on pad throughout movement. The long head (lateral head) of biceps brachii is activated significantly more than short head (medial head) of biceps brachii since short head enters into active insufficiency as it continues to contract. At bottom position, weight stack in use should not make contact with remaining weight stack.