By Jenni Rawlings, on Yoga International
Editor’s note: The following article is intended to provide general information for yoga practitioners and teachers. It is not a replacement for the personal advice of a health professional.
When considering shoulder alignment in downward facing dog, what are the first cues that pop into your mind? If you’re like most yogis, one of these cues is likely to be “external rotation.” With occasional exceptions, the instruction for the upper arm bone (humerus) to rotate externally in the shoulder socket (glenoid fossa) in down dog is a foundational alignment rule taught in most yoga teacher training programs.
Because the anatomical action of external rotation can be cued without actually using those specific words, there’s a chance you have been instructed to externally rotate your shoulders without even realizing it. You may have heard the suggestion in down dog to “wrap your triceps back,” “turn your armpits to face each other,” or “spin the eyes of your elbows forward.” These are all cues intended to create external rotation of the shoulder joint—and there are many more!
Why Externally Rotate?
Why is external rotation such a foundational alignment instruction in down dog? The main reason relates to shoulder safety. When we rotate the humerus externally as the arm lifts overhead (in what is called shoulder flexion), we create more space between the soft tissues of the shoulder joint and the “roof-like” bony structure of the shoulder blade (scapula) called the acromion process.