The shoulder or deltoid is made up of three muscular heads: anterior (front), medial (middle), and posterior (rear). Each head plays a different role in how the shoulder moves. The bent lateral raise mainly works the posterior portion of the shoulder, but each head assists with the movement. The exercise is also referred to as the bent reverse fly and rear lateral raise.

From a seated position, bend at the waist so that your chest is close to your knees. Grasp any form of weighted resistance and let the arms hang down. Slowly raise your arms outward until your elbows are even with the shoulders. The arms should remain in a fixed position at all times. The elbows do not have to be perfectly straight. Slowly return to the starting position and repeat.