Recently, I had an epiphany about my shoulders in handstand: my infraspinatus has been taking a vacation while I’m upside down! This blind spot and the lack of connection here has likely been hampering my ability to invert with confidence and stability for years! Of course, there are many factors involved in sticking a tight handstand, but it is vitally important that our shoulders are able to maintain proper alignment and provide stability while we’re balancing on our hands – or engaging in any weight bearing activity at the shoulders. And a key element to that is engaged, awakened external rotators, most notably (for me) the infraspinatus.
The Infraspinatus is one of four rotator cuff muscles whose function contributes to stabilization for the humerus in the glenoid cavity. It is also responsible for laterally rotating and adducting the shoulder at the glenohumeral joint. The infraspinatus orginates at the infraspinous fossa of the scapula (the flat surface below the spine of the scapula). It inserts on the head of the humerus.
To locate and feel the contraction of your own infraspinatus, reach your left arm across the chest and rest your hand on your right shoulder. Palpate with your fingers to find the spine of the scapula (which will feel like a horizontal speed bump reaching its way out toward the shoulder). Place your fingertips just below this bony landmarks, adduct your right arm as it hangs down and spin (ie externally rotate) your humerus back. As you create this DOM, feel your infraspinatus contract beneath your fingertips.
Understanding that the infraspinatus is not the lone player involved in external rotation and stabilization of the shoulder, it’s important to acknowledge some of the neighboring muscles that take a role in that as well. teres minor, subscapularis and supraspinatus also help to stabilize while teres minor along with the posterior fibers of the deltoid contribute to lateral rotation of the humerus. In addition, the serratus anterior plays an important part in shoulder stabilization as well, but that’s another topic to explore on another day. Although some of these other muscles of external rotation and stabilization may offer a great deal of contraction due to their size, if Infraspinatus is taking a siesta, or is unable to pull its weight due to injury, scar tissue, adhesions, or under-use, the whole picture is unbalanced and the shoulder is at greater risk of injury, especially during weight bearing postures, such as handstands, chatturangas, downward dog, arm balances, etc. I like to think of it like a puzzle – all the pieces are needed in order to create the whole.
So here’s my ‘spin’ on infraspinatus anatomy: With the recent discovery of a missing piece of my handstand picture, my work now is to awaken and strengthen my infraspinatus muscles in order to integrate them with the whole. Try the following YTU poses to activate and connect with yours!
– Holy Cow at the Trough with a block between hands – upon release, contracting the Infraspinatus, Teres Minor and Posterior Deltoid to keep the hands apart.
– Purgatory Dog
– Pin the arms on the yogi