The pectoralis major muscle is a large muscle in the upper chest, fanning across the chest from the shoulder to the breastbone. The two pectoralis major muscles, commonly referred to as the ‘pecs,’ ...

The shoulder muscles are responsible for maintaining the widest range of motion of any joint in your body. This flexibility is also what makes the shoulder prone to instability and injury. Muscles, ...

Your pectoralis major is a large and powerful chest muscle that’s shaped like a fan. It starts from two sections: your breastbone (sternum) and your collarbone (clavicle). The two sections come ...