Four Magic Muscles: Hidden Secrets to Core & Joint Stability
There are many magical muscles in the human body, but here are four that have been on my mind (and bodywork table) during the past couple months. This collection could also be called "missing muscles". When people see me for private sessions, we seek to discover and re-connect with muscles that have gone rogue.
Cultivate awareness of them, their attachments and movement contributions to feel better in your body.
Activating the Serratus Anterior for Shoulder Stability and Mobility
Attaching from the anterior/medial border of the scapula to lateral ribs 1-9, this muscle serrates with the ribs and the external oblique. It allows for harmonious scapular movement, but also works within the spiral line chain of movement. When you reach forward with your arms and feel the scapula come into protraction, serratus anterior is contracting.
Exploration: Lay on your back on the floor and slide your shoulder blades around your ribcage, reaching your hands toward the ceiling to explore your connection with serratus anterior. Change the angle you reach at to go deeper.
The Quadratus Lumborum and Core Alignment
The deepest muscle in the abdomen, QL is like a curtain between the ribs, transverse processes of the spine and iliac crest. It’s often much shorter on actual people than on model skeletons. Which is kind of funny when you see it. This muscle helps anchor the rib cage during breathing, hikes the hip and also does lateral flexion and extension of the spine.
Exploration: Stand on a step with one leg hanging off the edge. Elevate your hip bone toward your ribcage with a posterior (back side) focus to connect with the quadratus lumborum. Repeat this motion and explore both sides of your body.
Gluteus Medius Activation for Better Balance
This is one of the first regions I check on restorative motion clients because without glute med activation, stability and awareness you’ve got nothing to stand on, literally. This pair of muscles contracts every time you place weight on your feet and they counteract one another. This muscle divides into three sections and one of the three on at least one side of the body often needs focus and strengthening.
Exploration: Lie on your back with a band around your ankles or thighs. Slide one leg away from the other slightly into abduction and hold it. Try this in internal rotation, external rotation and neutral. Observe the right and left side differences and work with what you find.
Subscapularis: The Key to Happy Shoulder Joints
When rotation of the glenohumeral joint is of concern, checking in with this muscle, hidden deep under the scapula, can be very impactful. It can be challenging to access and connect with, but when the signal is sent it contributes to a happy shoulder joint. It’s main function is medial rotation of the humerus, which is often shortened from sitting in hunched postures, but sometimes being over-ridden by latissimus dorsi and pectoralis major - which are larger medial rotators.
Exploration: Lie on your back with your arm close to your body and place your elbow at 90 degrees. Rotate toward your body medially very gently so not to alert the larger lat and pec muscles. Press your arm into your torso or a towel on your abdomen to cause a contraction. Engage and tune into just the subscapularis.
Join the 2026 Anatomy Immersion in Bozeman
We explore these deep stabilization muscles and more in the Weekend Anatomy Immersion, using my signature 360-degree approach to human movement. Once a year, passionate movement practitioners, yoga teachers, and anatomy nerds gather for a truly unique, hands-on 3D anatomy training experience.
There are still a couple of spots left for our October 23–25, 2026 event in beautiful Bozeman, Montana. [Secure your spot today] to transform your perspective, your movement system, and your vision for the human body.
You can also dive into the magic muscles of the spiral line in the muscle mastery challenge. You will find serratus anterior in there with all of the other muscles in the movement chain of rotation.