"Stabilizer Muscles"

Interesting read if you have time.


QUESTION: There is nothing described as “stabilizer muscles” as a subspecies of muscle in Grey’s Anatomy. So why, then, has an entire training regimen has arisen that purports to train these muscles and that “only free weights” or lying on balls can accomplish this?

MCGUFF: (laughs) Oh that is one of the most irritating subjects of all to me. I think the whole concept of “stabilizer muscles” has been popularized mostly as a marketing ploy for different training concepts and different types of training equipment. And the whole concept of “core training” is a marketing mechanism for selling devices to train the abdominal muscles, which everyone seems to be fixated on. Most people are fixated on them because they have either an express or subconscious belief in the “spot reduction” theory. All that aside, every muscle in the body – from the flexor of your pinky finger, to your rectus abdominus muscle, to your trapezius muscle – any muscle that you name can be a “stabilizer muscle.” And the way that I think of it is that a muscle is either isotonically, meaning its contracting under load and shortening; it can contract eccentrically, meaning under load and lengthening, or it can contract isometrically, in which case the muscle is actively contracting but not producing movement. Any muscle that is contracting isometrically is acting as a stabilizer.

QUESTION: Right. And given the nature of muscular actions – the filaments slide together for contraction in a fairly linear fashion when they do contract – and when they do so against progressively increasing levels of resistance, they stronger. And it doesn’t matter whether that resistance is applied via a dumbbell, a cinder block or a Nautilus machine. In other words, there’s nothing intrinsically more beneficial in using free weights or rubber balls in developing the muscles that aid in stability and, in fact, you can probably train these muscles more efficiently and efficaciously by using, say, a Nautilus machine.

MCGUFF: Correct. The whole concept of “stabilizers” or bringing stabilizers into play while you’re actively working another muscle is just a romantic notion that really doesn’t bare out in reality at all – there aren’t “just stabilizer” muscles. Any muscle can be a “stabilizer” if it’s contracting isometrically to stabilize the body from any opposing movement in the opposite direction.


Gray’s Anatomy (not “Grey’s”…I think that is a TV show??) is not the best place to look for specific scientific data on muscle function. While Gray’s does contain some basic discussion of anatomical function, it is much more concerned with the details of anatomical structure.

There is a great deal of information about “stabilizer muscles” in the scientific (i.e., non-commercial) literature; however, one must look in the correct places to find it. High-level books on human kinesiology often summarize “stabilizer muscle” function, and very detailed accounts of specific “stabilizer muscle” function can be found via searching the medical journal literature.

In the arm, the triceps brachii is considered to be both a “stabilizer muscle” and a “decelerator muscle” during the act of overhead throwing.

See below for a description of the dynamic function of middle and lower trapezius muscles for stabilizing the scapula.

Rev. Brs. Fisioter. 2009 Feb 1;13(1):1-9.

Scapular and rotator cuff muscle activity during arm elevation: A review of normal function and alterations with shoulder impingement.

Phadke V, Camargo P, Ludewig P.

Program in Rehabilitation Science, Department of Physical Medicine & Rehabilitation, University of Minnesota, Minneapolis, Minnesota, USA.

OBJECTIVE: The purpose of this manuscript is to review current knowledge of how muscle activation and force production contribute to shoulder kinematics in healthy subjects and persons with shoulder impingement.

RESULTS: The middle and lower serratus anterior muscles produce scapular upward rotation, posterior tilting, and external rotation. Upper trapezius produces clavicular elevation and retraction. The middle trapezius is primarily a medial stabilizer of the scapula. The lower trapezius assists in medial stabilization and upward rotation of the scapula. The pectoralis minor is aligned to resist normal rotations of the scapula during arm elevation. The rotator cuff is critical to stabilization and prevention of excess superior translation of the humeral head, as well as production of glenohumeral external rotation during arm elevation. Alterations in activation amplitude or timing have been identified across various investigations of subjects with shoulder impingement as compared to healthy controls. These include decreased activation of the middle or lower serratus anterior and rotator cuff, delayed activation of middle and lower trapezius, and increased activation of the upper trapezius and middle deltoid in impingement subjects. In addition, subjects with a short resting length of the pectoralis minor exhibit altered scapular kinematic patterns similar to those found in persons with shoulder impingement.

CONCLUSION: These normal muscle functional capabilities and alterations in patient populations should be considered when planning exercise approaches for the rehabilitation of these patients.

Let’s see if you can grasp this concept: He is correct, yet it would be wrong to use Nautilus machines for sport-specific training.

Do you understand how both statements can be true?

Let’s see if you can grasp this concept: He is correct, yet it would be wrong to use Nautilus machines for sport-specific training.

Do you understand how both statements can be true?[/quote]