Chest Expansion (Arm Springs)
Plane of Motion
Sagittal & Transverse
Muscle Focus
Spring Setting
Light / Medium
Light or Medium Long Arm Springs
Shoulder Height Hooks
Shoulder Extensors
Latissimus Dorsi, Teres Major, Posterior Deltoid, Triceps Brachii

Scapular Depressors
Lower Trapezius, Serratus Anterior, Latissimus Dorsi, Pectoralis Minor

Scapular Adductors
Trapezius, Rhomboids, Levator Scapulae, Latissimus Dorsi (when arms are forward)

Scapular Downward Rotators
Rhomboids, Levator Scapulae, Pectoralis Minor, Latissimus Dorsi

Other Muscles at Play
Objectives
Enhance and extend the chest muscles by strengthening the midback, shoulder and arm extensors.
Challenge lumbo-pelvic stabilization while in a kneeling position.
Engage the mid and upper back while keeping the shoulder blades wide and lowered and avoid squeezing the scapulae together.
Proper arm and hand placement offers support and helps the body maintain the correct position.
Ensure that neck muscles remain relaxed and uninvolved when turning the head, while keeping the shoulder and scapula stable to loosen any neck tension on top of the stable shoulders and trunk.
Focus on breathing to synchronize the movement.