The rotator cuff muscles serve as part movers of the shoulders through various actions occurring at the shoulder joint, but most importantly, they’re critical to primarily maintaining “stability” and control at the shoulder while the outer, more prominent, and more powerful perform a majority of dynamic motion. Failure to properly “centrate” or center the ball of the humerus inside the Glenoid Fossa (socket) will render eventual injury to either the labrum, capsule, and or various connective tissues and muscles located throughout the shoulder. So yes, you could say that the rotator cuff is vital to shoulder survival!
THE MOBILITY MYTH!
Whenever there is a discussion on the shoulder, specifically, most authorities advocate making sure that the shoulder remains highly mobile to prevent further or future injury. According to the shoulders natural design, it is supposed to be mobile, but you can also have too much of a good thing and neglect control, and then eventually you are doomed. So, in essence, mobility comes first, and stability follows in a close second. You could even argue that lack of stability is more common due to the over promotion of mobility and a lack of attention on learning how to control the joint properly. Before we continue, if the upper back (thoracic spine) is locked up, and you lack proper retraction and upward rotation of the shoulder blades, along with full range shoulder flexion, then bad things are going to happen at some point. But then again, even in the presence of healthy ranges of motion at the shoulder, you will still witness time and time again, people complaining about nagging injuries, aches, and pains. So what gives?
The issue folks is often a lack of motor control in the shoulder from the repeated failure of the specific muscles at the joint. Hypermobility and laxity can also cause extreme looseness at the joint and subsequent problems, so be wary of that as well. Here is a good test series to see if you may suffer from severe mobility, which could be causing you problems:
In the second part of this blog I will provide you with simple tests and movements to determine whether or not you need to incorporate more shoulder flexibility/mobility work into your training regime so stay tuned for that. For now, I want to highlight a particular muscle that is critical to supporting the structural integrity of the shoulder. Enter “The Subscapularis!” The Subscapularis carries the inherent burden of having to compete with some serious mass across the front of the shoulder, and more often than not it will lose that battle because it has a smaller CSA (Cross-Sectional Area), or bulk which naturally puts the muscle at a mechanical disadvantage in the grand scheme of things. The Lats, pecs, and anterior deltoid attempt to draw the ball of the upper arm forward and upward into the socket, which can pose several problems. All the while, the Subscapularis, and few other small cuff muscles attempt to keep the ball down, but often fail. So what can you do to help your cause in maintaining or regaining control of your shoulder joint?
Here is a video that details a drill compliments of Eric Cressey to help activate the Subscapularis: