Shoulder stretches are necessary to maintain a balance among the muscles around the shoulders and upper back. As gravity pulls us forward and things in our life that demand our attention pull us forward, the muscles on the front of our chest and shoulders shorten. These forces cause disc degeneration, head and neck pain, rotator cuff impingement, amongst other problems. Regular shoulder stretches can improve posture, improve function, and make us feel and look younger. For a lot of us stress in our lives is manifested by tightness and hyperactivity of our shoulder muscles.
There are five major pairs of movements at the shoulder: (1) flexion and extension, (2) abduction and adduction, (3) external and internal rotation, (4) retraction and protraction, and (5) elevation and depression. The bones of the shoulder joint consist of the humerus (upper-arm bone), scapula (shoulder blade), and clavicle (collarbone). The scapula and clavicle essentially float on top of the rib cage. Therefore, a major function of many upper-back and chest muscles is to attach the scapula in the upper back and the clavicle in the upper chest to the rib cage and spine. This provides a stable platform for arm and shoulder movements. Of the five movement pairs, retraction and protraction and elevation and depression usually are classified as stabilization actions.
It is vital to maintain proper balance between strength and flexibility in all shoulder muscles. The common problems associated with the muscles of the shoulders, back, and chest are tight muscles and muscle spasms in the neck (middle and upper trapezius), shoulder (trapezius, deltoid, supraspinatus), and upper back (rhomboids and levator scapulae).
The tightness felt in these muscles is usually a result of initial tightness in their antagonist muscles. In other words, tight muscles in the upper chest caused the tightness felt in the upper back. Tight chest muscles (e.g., the pectoralis major) cause a constant low-level stretch on the muscles of the upper back. Eventually, this low-level stretch elongates the ligaments and tendons associated with the upper-back muscles. Once these ligaments and tendons become elongated, the tone in their related muscles falls intensely. To regain the lost tone, the muscles must increase their force of contraction. Increased force in turn causes more stretch of the ligaments and tendons, and increased muscle contraction must compensate for that. Hence, a vicious cycle starts therefore the best way to prevent or stop this cycle is to stretch the anterior shoulder and chest muscles.
As the flexibility of these muscles improves, the tightness of the posterior muscles is reduced. Immediately after stretching, the strength of the muscles is reduced. It is a good idea to stretch the opposing muscles just before and immediately after working any group of muscles.