Death, taxes and shoulder pain; everyone has to deal with these issues at some point in their life. After low back pain, shoulder pain is the second most common complaint in the work force. And that’s in a sedentary environment. The risk increases when you place someone in a gym and add hundreds of pounds of force on the shoulder joints. That’s because the shoulder area is the most complex region of the body. It’s also due in part to poorly designed training programs, strength imbalances in and around the shoulder, and improper loading of the shoulder girdle. As a result the price that is paid usually ends up being an injury.

Whether you’re a competitive athlete, an avid strength trainer, or someone involved in a power sport, you can be sure the shoulders will take a beating. The key to ensuring that the risk of injury to the shoulder complex decreases is to have a firm grasp of what precautions should be taken to strengthen the shoulders, and to fit them into your current program.

A basic understanding of what the muscles in and around the shoulder do can be helpful in diagnosing and treating weaknesses and in preventing injury. The shoulder is comprised of several joints that combine muscles and tendons that allow for a wide range of motions to occur. If you’ve heard of the rotator cuff, then you might know what they do. They are four muscles that act to stabilize the glenohumeral joint (which is one of the four joints of the shoulder region that work together to create a controlled movement in the shoulder complex).

The four muscles of the rotator cuff (and their function) are as follows:

The other muscles of the shoulder are the posterior delt, the anterior delt, the side deltoid, the caracobrachialis, the pectoralis major, the latissimus dorsi, and the teres major. Other muscles of the shoulder girdle are the trapezius, the rhomboids, the levator scapulae, and the serratus anterior. Synergist arm muscles include the triceps brachii, and the biceps brachii.