Major Muscles and Actions Involved
The anterior deltoid, the pectoralis major (upper portion), and the coracobrachialis are involved in the front arm raise. The action in this exercise is shoulder joint flexion, in which the arms move directly forward and upward from a position alongside the body. In the shoulder girdle the serratus anterior and the upper and lower trapezius are involved in upward rotation of the scapula. When both arms are involved, the right scapula rotates counterclockwise and the left rotates clockwise on an axis through the center of each bone when viewed from the rear. When one or both arms are used, the scapula also undergo some abduction, especially in a reaching action, in which they move away from the spine toward the sides of the rib cage.
Muscles in Action
Sports Uses
Shoulder joint flexion and the muscles involved are most important in sports that require you to move your arms up and in front. This includes gymnastics and diving, and basketball and volleyball when you reach upward to get or block the ball. They are also needed in boxing to get and keep the arm up and in the uppercut, and in judo, wrestling, and other sports. However, most often these movements are not done against a heavy resistance.
Important Facts to Know
- It is important to understand that the deltoid muscle is most active from approximately 45-degree below the horizontal to 45-degree above the horizontal. It is not active in the initial movement when the arms are alongside the body up until about 45-degree above level.
- The main muscle in the early stages of movement is the supraspinatus, not the deltoid. This is why if you want full development of the deltoid you must go through a full ROM with the arms overhead. Stopping at a level position does not tax the deltoids to the same extent.