Muscle · Chest

Pectoralis major

Musculus pectoralis major

The big fan of the chest, arising along the collarbone, the breastbone and the upper rib cartilages and converging on a flat tendon at the front of the upper arm bone. It draws the arm across the body and rotates it inward — the bench press, the hug, the throw. Its two heads pull in different directions through part of the range: the upper head lifts the arm forward, the lower head pulls it back down. Momentum's clinical system names tight chest muscles as a direct cause of shoulder pain, and its shoulder flow opens by releasing them.