Which muscle is commonly called the "boxer's muscle"?

The serratus anterior is commonly referred to as the "boxer's muscle" primarily because of its function in the motion of punching and other athletic movements that involve shoulder protraction. This muscle is situated on the side of the ribcage and plays a crucial role in stabilizing the scapula during arm movements. When a boxer throws a punch, the serratus anterior assists in pushing the arm forward and keeping the scapula stable, allowing for effective and powerful strikes.

In addition, the serratus anterior's involvement in overhead motions and its contribution to the overall mobility and strength of the shoulder girdle make it particularly vital for sports that require rapid and powerful movements, such as boxing. The activation of this muscle allows for better reach and control, enhancing performance in activities that demand upper body strength and coordination. This anatomical and functional significance is what leads to the nickname "boxer's muscle."