What is the role of the pectoralis major muscle?

The pectoralis major muscle plays a significant role in the movement of the shoulder, particularly in flexion and adduction. This large, thick muscle is located in the chest and extends from the sternum and clavicle to the humerus. Its primary functions include pulling the arm toward the body and assisting in raising the arm. This is crucial for actions such as reaching forward or bringing the arms across the chest.

In context, while stabilization of the spine, support for the abdominal wall, and connection between the humerus and scapula are important functions of various muscles in the body, they do not pertain specifically to the primary actions of the pectoralis major. The focus on movement, particularly its role in shoulder flexion and adduction, highlights its importance in upper body mobility and many daily activities as well as various athletic actions.