Pectoralis Major
Chest & Trunk
The 'bench press' muscle — and it's the one bodybuilders love to bounce.
Function
Flexes, adducts, and internally rotates arm
Origin
Medial clavicle, sternum, costal cartilages 1-6, aponeurosis of external oblique
Insertion
Lateral lip of intertubercular groove of humerus
Innervation
Medial and lateral pectoral nerves (C5-T1)