There are four muscles that make up the rotator cuff: Teres Minor, Infraspinatus, Supraspinatus, and the Subscapularis. In simple terms, these four muscles connect the arm bone to the shoulder blade and collarbone. They help in maintaining proper position of the two joints that make up the shoulder: the glenohumeral (GH) joint and the acromioclavicular (AC) joint. They can assist with internally and externally rotating the arms. Another role is in decelerating arm motion (slowing the arm down after throwing a football). It is with this deceleration that the rotator cuff combats the greatest amount of force. If it didn’t, your arm would likely dislocate.
It is not just the rotator cuff that is responsible for decelerating arm action. They are the smallest muscles in a chain of connective tissue that are involved. The latissimus dorsi, thoracolumbar fascia, gluteus maximus, hamstrings, and the calves are the biggest decelerators when it comes to forward arm motion. Wait a minute, the glutes, hamstrings and calves aren’t attached to the arm. That is true but the arm attaches to the shoulder blade which attaches to the rib cage which attaches to the pelvis which attaches to the thigh and then the lower leg and eventually the foot; just like the old song, “The knee bone’s connected to the hip bone…” That means when the arm moves forward the shoulder blade, rib cage, pelvis, femur, knee and lower leg are all involved in a chain reaction to decelerate the body. A simple example would be a casual arm swing when walking.
What is required for efficient deceleration is joint mobility, motor control, and muscular flexibility. Joints must move through their proper range of motion while the nervous system creates dynamic stability and muscles lengthen and shorten without any hindrance. Each link in the chain reaction for decelerating the arm is responsible for a certain percentage which always equals 100%. Unfortunately if a person has shortened (tight) gluteals, hamstrings, calves or lats, the percentage of demand lessens in those areas and increase dramatically on the rotator cuff muscles.
Which begs you to wonder why you see so many people doing rotator cuff exercises with rubber bands if that area is already being beat up due to other muscles not doing their job. Wouldn’t it make more sense to teach the proper chain reaction for arm deceleration by involving all of those big muscles of the torso, hips, and legs? Teaching the lats, gluteals and hamstrings to lengthen would instantly reduce any excessive demand placed on the rotator cuff.
We have to break away from the traditional close-minded approach where all the focus and attention is placed on the victim, the 99-pound weakling, and not on the culprit. The human design is not flawed. We do not need to develop huge rotator cuff muscles. We need to understand how the body moves as an integrated unit and encourage efficiency of movement. So put down the rubber band or 2-pound dumbbell and explore how flexible the muscles around the shoulder girdle, the hips and thighs are. You will most likely find that as you improve these areas your rotator cuff starts to sing rather than scream. [/columnize]