The four muscles and their tendons that make up the Rotator Cuff of the shoulder are, probably, the most misunderstood, taken for granted AND frequently injured muscles in the body.
And the injuries that afflict these muscles and their tendons, not only tend to be serious and debilitating, but difficult to recover from, so whether you’re an athlete, like a golfer or tennis player, a weightlifter/bodybuilder or simply someone doing Rotator Cuff rehab exercises, keep reading…
This is an essential, if not critical, area of importance for Tennis Elbow and Golfer’s Elbow sufferers, too! Which is why I’m writing about it here.
There is a significant link between Rotator Cuff weakness and/or injury, and Tennis and Golfer’s Elbow injuries. (Having a lot to do with adaptations / compensations “downstream” in the forearm from rotator weakness and other issues above in the shoulder.)
It’s not the easiest thing to recognize on ones own – but once you’ve made significant progress in recovering from your elbow injury and are well on your way to strengthening the muscles involved in your elbow tendon injury, locally…
Then consider adding Rotator Cuff exercises to your rehab program, and keep at them LONG TERM! (Which is what I always suggest to the clients I work with in person at my clinic, and to my members here at Tennis Elbow Classroom.)
In the video below, Jeff Cavaliere, a Physical Therapist for pro athletes, describes the function of the four muscles of the Rotator Cuff, dispelling several myths he runs into about them and offers excellent suggestions on avoiding several mistakes when it comes to exercising the Rotator Cuff.
His message seems to be mainly directed at athletes, who do a lot of weight training, but it has some key points I want to discuss and elaborate on in the rest of this article.
The Four Muscles Of The Rotator Cuff And Their Functions
The Rotator Cuff is a term for a group of four muscles, all originating from the Scapula “shoulder blade,” the tendons of which all come together around the front, top and sides of the shoulder joint to form a continuous sleeve, or what looks like an upside-down “U”-shaped “cuff.”
These four muscles and their tendons are:
- The Subscapularis – (front of Scapula) internally rotates the shoulder,
- The Supraspinatus – (top of Scapula) abducts the shoulder; and two muscles,
- The Infraspinatus – (back of Scapula, above Teres Minor) AND
- The Teres Minor – (back of Scapula, below the Infraspinatus) both of which are external rotators of the shoulder
Clearly, these muscles have a function when it comes to rotating the shoulder joint internally and externally, (forward and backward) hence the name.
However, despite the fact that these muscles have these independent functions, and can be targeted with individual exercises (as they should be)…
The Primary Function Of The Cuff Is NOT Movement!
The PRIMARY function of the Rotator Cuff is to stabilize the main shoulder joint, the Glenohumeral Joint, and to keep the head of the Humerus (the “ball”) positioned / centered in the Glenoid Fossa (AKA, the “socket,” which is more like a shallow dish than a socket.)
The shoulder is the most mobile joint in the body, having the largest range of motion (ROM) which makes this joint the most vulnerable to injury.
The shoulder joint itself is not inherently stable (not rigid or fixed in any plane of movement, like the simple hinge joints of the knee and elbow, which mostly allow movement in only one plane; they bend and straighten / flex and extend, exclusively.)
One of the points Jeff makes in the video is that, in his experience working with athletes, most of their weight training is devoid of Rotator-Cuff-specific exercises.
My own experience from decades of watching people – and especially Personal Trainers at my gym – is that there is not enough emphasis on this key muscle group (if any!)
And when I DO observe people doing these exercises, they are, more often than not, doing them incorrectly – Dangerously, even!
I’m not going to cover all of Jeff’s 5 myths here, but from my perspective, the most important point covered, is the risk involved in an exercise that is often suggested for the Supraspinatus muscle.
The Risks Of The ‘Empty Can’ Supraspinatus Exercise
The ‘Empty Can’ exercise is intended to isolate the Supraspinatus muscle (as much as possible) – is often recommended by Physical Therapists / Phsyiotherapists [Article on Physical Therapy for the treatment of Tennis Elbow]
The ‘Empty Can’ exercise involves abducting the shoulder (raising the arms out to the side and away from the body ‘laterally’ – and somewhat forward in front of the body) in this case with the elbows fully extended (straight.)
A fairly light weight is held in the hands – and the key distinction with this exercise is that instead of allowing the shoulders to externally rotate slightly (which is the natural thing to do, as one abducts and/or flexes the shoulder joint)…
One forces and keeps ones shoulders in an internally rotated position (rotated forward – instead of neutral or allowing external rotation) as one abducts / raises ones arms out to the side.
AND ones wrists pronated (hands turned palms down, thumbs pointed toward the floor) as if one was holding a bottle or can that one was pouring out.
(Imagine the weightlifter in the image above but with his thumbs pointed down rather than up and his arms out to the sides considerably more.)
This is a terrible position for the Supraspinatus, because the internal rotation while abducting leads to the unnecessary risk of decreasing the space the Supraspinatus Tendon has between the head of the Humerus (ball of the shoulder) and the Acromion Process of the Scapula (the “shelf” just above it.)
And, subsequently, increasing the potential compression and friction on the tendon and the risk of wear and tear on it.
The Supraspinatus is the most vulnerable muscle and tendon of the Rotator Cuff – and shoulder, in general, and the most frequently injured.
It is the tendon that gets affected by Bursitis and gets ‘impinged’ – And it’s the most common site of tendon degeneration and fraying/tearing.
And the Supraspinatus, unfortunately, claims the dubious distinction as the site of the second-most-common Orthopedic procedure in the US, following arthroscopic repair of the knee.
Jeff, demonstrates a much safer exercise in the video, known as ‘Scaption’ to work the Supraspinatus, which is a mix of shoulder abduction and flexion, with the weights held in a neutral wrist position (thumbs pointed up) and NO internal shoulder rotation.
I will point out that there is another exercise for the Supraspinatus, one can do if one has access to cable equipment at a gym or at home.
(I will post a video or link to a video on that exercise later.)
Because this is not an ideal exercise to do with bands, which are often used by trainers and therapists to demonstrate Rotator Cuff exercises and recommended to clients and patients as an easy way to do them at home.
The amount of resistance bands provide, changes as one moves through the exercise’s range of motion – beginning with less and increasing as one executes the motion.
This is okay for training some muscles, but I believe the tendons of the Rotator Cuff Muscles, in particular, benefit from a constant, steady resistance.
Building coordination through SLOW, consistent resistance throughout the range of motion is key.
And ONLY through the safe and easy range of motion – without trying to “push” the range of motion – OR use the tension of the resistance as a “stretch” at the beginning or end of the range (too risky and not the point of the exercise!)
Lastly, I have a disagreement with Jeff (or a partial disagreement, anyway) over his second myth, the idea that one needs to train the entire Rotator Cuff.
Do You Need To Train The Whole Cuff – Or Not?
Jeff believes it isn’t necessary to exercise the Subscapularis directly (the internal shoulder rotator.)
“..the internal rotation function of the shoulder is more than adequately handled by the contributions of the lats and pecs to internally rotating the joint.”
“Throw in more direct rotation exercises and you are just furthering the imbalance that already exists and is causing your shoulder to be dysfunctional in the first place.”
This may be applicable to athletes who are training every major muscle in their upper bodies, utilizing multiple exercises.
The “lats” (Latissimus Dorsi) and to a lessor extent, the “pecs” Pectoralis Major (not to mention the Teres Major) are internal rotators themselves.
And perhaps it does make sense for this subset of people (whom Jeff is primarily speaking to) to skip working the Subscapularis directly and instead let it get worked by way of those other movements/exercises.
His concern is that with so much emphasis on these major shoulder muscles, which internally rotate the shoulder, and which have a mechanical advantage and tendency to be dominant…
That more emphasis will only exacerbate an imbalance where the inherently “weaker” external rotators are overpowered mechanically (and neurologically, I will add, though a process known as ‘Reciprocal Inhibition’ – I don’t remember if he mentioned that. I know he knows that concept.)
However, I have two points:
- This may not really apply to people who don’t normally do a lot (if any) upper body strength training – And are not at risk for this dynamic… People whose primary goal is more basic or rehab-focused – whether to recover from a shoulder injury OR to correct a biomechanical issue that’s contributing to a “downstream” adaptation / compensation – Like Tennis Elbow or Golfer’s Elbow
- And I believe there is still a case to be made for targeting the Subscapularis directly (for everyone) with “pure” internal rotation (although maybe with less emphasis – Just 1 set instead of 2, perhaps, with 2 sets for the other muscles?)
I may not be able to prove this, but I believe that isolating and exercising the Subscapularis (and all the other Rotator Cuff muscles and tendons) may be necessary to keep it functioning at its fullest…
Hitting the “Subscap” with multiple sets and using ever heavier weight / greater resistance? Probably not necessary for most people.
It doesn’t necessarily need to get a lot stronger in some people – but it does need to remain functional and coordinated.
Some targeted exercise in order to condition and strengthen the Subscapularis tendon and avoid dysfunction has to be a good idea!
Especially for people who need maximum shoulder coordination, strength and flexibility.
I’m thinking golfers, tennis players (and other racket sports enthusiasts) swimmers and anyone involved in a paddle sport or activity (which is my big passion.)
Rotator Cuff dysfunctions are notoriously common in this group, including degeneration, fraying, bursitis, (which affects/involves the Supraspinatus) impingement and tearing.
Not to mention that insidious, chronic degeneration is all-too-common in the aging population at large.
However, most of it IS preventable – as well as treatable, after the fact – with proper Rotator Cuff strengthening and treatment
(Which, should, ideally, include hands-on manipulation / ‘Manual Therapy’ / Advanced Massage Therapy Techniques.)
If you’re here because you’re looking into how your Rotator Cuff, and it’s weakness or other issues may be contributing to your Tennis or Golfer’s Elbow AND you are not already familiar with my programs for Golfer’s and Tennis Elbow, here’s where you can learn more:
Learn To Treat And Heal Your Own Tennis Elbow Or Golfer’s Elbow At Home With This Video Program
I’ll be your personal tutor guiding you through step-by-step video lessons, where you’ll get the therapy techniques, key stretches and essential exercises you need to treat and recover from your injury at home. (Without any special equipment.)
Tennis Elbow sufferers: Learn more about the program here
Golfer’s Elbow sufferers: Learn more about the program here