This morning we’re going to delve into the musculature of the shoulder complex. Whether it’s bringing a fork to our mouth, catching a ball, or blocking our face from objects, we can see that the musculature of the head and shoulder are closely tied to the sensory system of the head and face. These simple movements are orchestrated and complex, requiring a large amount of neuromuscular control. The more muscles recruited, the more synapses fired, utilizing a greater expand of the spinal cord.
Scapular stabilizers include a number of different muscles. To start we’ve got rhomboid major and minor, upper trapezius and lower trapezieus, which rotate and position the head of the humerus in the glenoid fossa. We’ve also got levator scapulae originating on the superior border of the scap and inserting on C1, 2, &3. Finally serratus anterior (SA) rooting off the ribcage, below pec minor, and behind scap. It protracts the shoulder, pushing it forward. If we carry this over to a practical movement, throwing a ball for instance, SA brings the shoulder forward, in our rack or catch position during our front squat or clean, we’re getting huge SA recruitment to stabilize the head of humerus in the fossa. Serratus anterior is a phasic muscle, which means with trauma it lengthens and weakens, causing surrounding musculature to pick up its slack. These compensatory muscles are tonic muscles and they are pec minor, levator scapulae and upper trapezieus. Tonic means the muscles have shortened and tightened due to a phasic muscle lengthening and weakening.
If we look at the athletic population, crossfitters, hockey, swim, you name it, a lot of times they are drawn forward into that anterior flexion/rolled shoulder posture, a good indicator that they probably have some tonic and phasic muscle action happening. In order to get the most out of our specilizations we have to re create muscle balance, lengthen short and tight muscles, and strengthen/stabilize long and weak muscles. Rooting back to the foundation of the optimal performance pyramid. Before we add strength and power to a system we need to correct, or activate muscle balance and symmetry.
If we peel away our superficial tissues and go deeper into the musculature of the shoulder girdle we can dive into the nasty rotator cuff. Subscapularis is attached on the front side or ventral side of the scapula and is a primary medial rotator. Her antagonists are infraspinatus and teres minor. Supraspinatus is commonly injured, torn or impinged. Subscap, infraspinatus, and teres minor act to cradle and hold the head of the humerus in the fossa, while supraspinatus depresses and pushes the head of the humerus down, so with Abduction, we don’t get impingement of the supraspinatus or biceps tendon on the bursa.
Pec minor, another nasty problematic site, attaches from ribs 2, 3, &4 on to the caracoid process of the scapulae. Due to it being a tonic muscle, when there is trauma or injury to the shoulder girdle, it’s faulty state is short and tight, pulling the shoulder down and tipping the shoulder forward. Again giving us that “athletic” rounded shoulder syndrome, a posture that isn’t so athletic. changing our shoulder posture, changes our trunk and low back alignment as well, leading to excess kyphotic T-spine and excess lordosis through the lumbar. Practical application of this not so ideal body posture is exacerbated in our dead lift. When an athlete hinges with poor posture, they are hanging on to the weight with just hamstrings, which can be problematic, leading to facet joint problems, spondylothesis, pars fractures, SI dysfunction and other low back/glute issues. Pec minor is our workaholic muscle, always on, never taking a day off. We gotta send her on vaca every once in a while to get back to normal posture and movement.
We’ve also got deltoid and pec major, biceps, tricpes and latissimus dosri. I was watching a Kelly Starrett mobilitywob yesterday and he said it best, a lot of people spend a lot of time with trigger point work on both deltoid and pec, neglecting the posterior and inferior aspects of the shoulder. By getting under those big prime movers and hitting some of our shoulder extensors (SA, lats, infraspinatus) we can see a tremendous increase in our overhead mobility as well as our extension range of motion. By reducing tone in these posterior muscles, and giving them a little bit more juice, enhancing nerve supply and synaptic potential, this transfers over into improved shoulder stability, enhancing your dead lift, front squat, clean, and jerk. All primary movements for increasing power and strength for any athletic setting.
Biceps and triceps have gotten a bad rap as being our “look good” muscles, am I right? We’ve all head, ”curls for the girls!”. What we need to look at is their supporting role to your shoulder stability and strength. Biceps provide a ton of support for the front of the shoulder. Looking at our rack position again, it requires a ton of strength and stability up top, as shoulder stability and strength contributes to holding your trunk and core upright in our receiving positions. We’ve got a picture of Natalie Burgener below, her biceps have a high neuromuscular innervation rate in this bottom position, not to mention how active her triceps are, as they are providing support on the posterior aspect of that shoulder complex.
Last but not least, latissimus dorsi, a powerful extensor of the shoulder and medial rotator, attaches from the spine into the bicipital groove of the humerus. Its direct linkage with the spinal cord provides this muscle with an open communication policy between the spine and the shoulder. Linking our central and peripheral nervous system. I think that looking deeper into this central/peripheral relationship can really broaden our training approach and our recovery days/methods.
At the beginning of the article I mentioned how there is a huge connection between the shoulder and our head/spinal cord, and coming back full circle to that, if we take a look at levator scapulae and omohyoid, we get a much deeper understanding of this linkage.
Back in the ’70′s, Dr. Chez, head of the cornosine autism trials in Chicago, linked the limbic system to trigger points in upper trapezius and levator scapulae. The limbic system is the control center for our emotions and feelings and what Dr. Chez found, was that with heightened activation within the area of the brain where the limbic system is located, patients exhibited increased tone and tension in upper traps and levator scapulae. These muscles in humans are compared to the hood on a cobra snake, when the cobra goes into a fight or flight state, the hood flares. The same is said for humans, when we are under stress, increased anger, or fear, this emotional response takes on a physical manifestation. We can see that there is a direct relationship between shoulder girdle issues and stress. Now when it comes to your performance, something you should ask yourself , are these physical manifestations secondary to emotional problems? We could spend another blog discussing the relationship to over training and why rest and recovery is so important, not just for strength and power gains, but for overall injury prevention, and mental wellness.
Lastly, to conclude this, omohyoid muscle, attaches from scapula to the hyoid bones, and when we breath aggressively, we can see them protrude from our neck. Their attachment sites alone illustrate to us the relationship that they have in regards to shoulder function and our sympathetic nervous system through our breath. When we inhale, omohyoid picks up the lunge, to aid in inhalation, avoiding collapse of the lunge. If we look at the common rounded shoulder posture, tipping the scapula forward is going to tighten this muscle. Changes in the omohyoid length:tension relationship could change swallowing and breathing mechanics, disrupting our sympathetic nervous system, increasing compensation and systemic movement dysfunction.
Take away from this article:
Release tonic muscles, stabilize phasic muscles. If it’s long and weak give it support, short and tight, lengthen it out. The body is a complex system, everything is connected. Improving performance isn’t just about physical modifications but we need to look deeper at our nervous system response and activation, mental wellness, and overall well being.
Stay connected for more to come on Scientific Shoulder Stuff You Should Read.