By MICHAEL CHIN|DPT, CSCS
What makes the shoulder a great joint is that it can move in three different planes and has a wide range of motion. However, the shoulder’s strength is also its weakness.
Shoulder pain is a common complaint of CrossFitters. There can be a plethora of causes for shoulder pain, including soft tissue pathology, biomechanical deficits, structural damage, and anatomical abnormalities. Without having a formal evaluation, I cannot say what the origin of your shoulder pain is, but hopefully — by tackling some of the more common causes of shoulder pain — we can get you back to doing presses, pushups, pullups, cleans,snatches, handstands, and muscles-ups without pain.
To understand the purpose of certain exercises for the shoulder, you need to understand the basic anatomy and biomechanics.
Shoulder Anatomy & Biomechanics
What makes the shoulder a great joint is that it can move in three different planes and has a wide range of motion. However, the shoulder’s strength is also its weakness, as several components need to work in harmony to produce a full painless range of motion. Approximately 17 muscles working in conjunction with the scapula and humerus bones will produce most of your motion. If you’re a member of the legion of supple leopards, you’ll understand that there needs to be adequate clavicular, lumber, thoracic, and cervical spine mobility to produce full overhead movement as well.
What is full overhead movement? At the box, it’s the difference between a counted rep versus a no rep. But if you want to take out your goniometer, it’s 180 degrees of flexion and abduction.
Science note: For every 2 degrees of humeral movement, there is one degree of scapular upward rotation.
We have all these bones and muscles working together just to get that darn weight overhead, but I’ll try to break it down as simply as I can: The scapular must move synchronously with the humerus for overhead movement. This is called scapulohumeral rhythm. A simple number to know is that there is a 2:1 ratio of humeral to scapular movement. For every 2 degrees of humeral movement, there is one degree of scapular upward rotation. Once you get to approximately 150 degrees of elevation, which is most likely a no rep, the scapula must posteriorly rotate; the thoracic spine must extend; and there must be some lumbar extension as well (keep that core tight!) to reach that full range of 180 degrees. Proper scapulothoracic rhythm is necessary, as it maintains optimal muscle length and contraction of the rotator cuff muscles — the stabilizers of the humeral head in the shoulder socket.
Of the many muscles working together to produce normal scapular and humeral movement, we can organize the muscles into distinct groups:
Scapular pivotors
Humeral Propellers
Humeral Positioners
Shoulder Protectors
- Rotator cuff (Supraspinatus, infraspinatus, teres minor, and subscapularis)
- Long head biceps
You can mobilize your shoulder to achieve a full range of motion.
Okay, so now what? If you’re having shoulder pain with overhead movement, my advice is to rest and avoid activity that creates pain. During this rest period, we’ll focus on mobility of the joints affecting shoulder elevation (assuming there is some limitation here). In next week’s piece, we’ll address the accessory work of targeting and re-educating specific muscles listed above to improve shoulder mobility.
Shoulder Exercises for a Full Range of Motion
External Rotation
This motion goes hand in hand with elevation of the arm to reach full elevation. Try this: turn your hands and arms inward (internal rotation, bad position!) and then try to elevate the arm. Not only will it be difficult to reach full elevation, but you might also have some pain. There can be some limitations in external rotation since the internal rotators of the shoulders (subscapularis, anterior deltoid, pectoralis major, latissimus dorse, and teresmajor) have a much greater muscle mass. Stronger doesn’t always mean tighter, but this tends to happen.
Instruction:
Have the arm in a 90-degree abduction and 90-degree elbow flexion position. Put the PVC directly under the armpit, which will be used as the fulcrum. Use the bottom arm to rotate the 90/90 arm backward, or in external rotation. Keep a tight core and don’t allow arching of the spine!
Internal Rotation
If you don’t have adequate internal rotation, the scapula will compensate into a forward rounded position. Forward shoulders is the opposite of what we need for overhead movement, so this is a poor position to hang out in. (Think about how many hours a day you may spend in this position if you don’t have good posture.) This can predispose you to injury, shoulder impingement and tendonitis in particular. Along with this problem, the humerus may sit in a forward position as well, changing the arthrokinematics of the shoulder.
Instruction:
The “sleeper” stretch is used to increase internal rotation and stretch out the often tight posterior capsule. Lay on the side of the arm you are going to stretch. Similar to the external rotation stretch, get into a 90/90 position. Use your other arm to bring your wrist down towards the ground.
Pectoralis Major
This muscle acts to bring the humerus towards the body, medially rotate, and bring the scapular forward and down.
Pec Minor
This muscle stabilizes the scapula against the thoracic wall and brings the scapula forward and down.
Problem: If these muscles are tight, they can restrict arm elevation through both the humerus and scapula. Sit at a desk a lot? Are your shoulders positioned in front of your ears? If so, you likely have tightness in these muscles and will benefit from the “doorway” stretch.
Instruction:
Stabilize the forearm against a wall (or in this case, a pole on a rig) and slowly bring your body weight forward. Stretch at two different positions to target the different fibers of the pec major and minor.
Levator Scapulae
This muscle tilts the scapula inferiorly, pointing the shoulder down. With shoulder elevation we want the opposite. If this muscle is tight — which is common with athletes, and the general population for that matter — it can restrict overhead movement. (Check out Dr. Missy Albrecht‘s “Muscle Spotlight” article on levator scapulae here.)
Instruction:
Stabilize the arm overhead by holding onto rings, a bar, or even a doorway. I like the rings because it gives a little more external rotation and allows the arm to get close the head. Rotate your head the opposite direction 45 degrees, then bring your head straight down. Use your other arm to apply overpressure.
Teres Major
This muscle acts to bring the arm in towards the body, which is obviously the opposite of elevation. You might get the teres major stretched just by hanging from a bar or with the other stretches requiring the arm overhead, but since it’s attached to the scapular, if it is very tight your body may compensate by producing excessive scapular rotation.
Instruction:
Lay on your side with a foam roller over the outside edge of the scapula. Roll down slightly and allow the arm to elevate. By stabilizing the scapula, we can target the teres major better.
Thoracic extension
The thoracic spine does have a normal flex shape, or kyphotic curve as we call it. The problem is that gravity often takes over and increases that curve, which works against the normal motion needed to produce arm elevation. The thoracic spine should have some mobility into extension to allow full overhead positions.
Instruction:
Lay on your back with your butt on the ground and foam roller under your upper back/thoracic spine. Have your hand behind your head and neck flexed slightly. Extend the upper back while keeping the butt down and head and arms in the same position. Don’t extend the neck! You should feel a stretch sensation in your chest as if it was expanding.
Stay tuned for next week’s piece on exercises to strengthen specific muscles of the shoulder.
References
M Dutton. Dutton’s Orthopaedic Examination, Evaluation, and Intervention. 3rd ed. McGraw-Hill Companies, Inc. 2012
KL Moore, AF Dalley, AM Angur. Clinically Oriented Anatomy. 6th edition. Balitimore, MD. Lippincott Williams, 2010.
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