Pirirformis Paradox

Have you ever thought about why one stretches pririformis muscle in pigeon pose while it is a positioning of an utter lateral (external) rotation of a thigh? But a piririformis is a lateral (external) rotator by itself. So, to stretch it one need to position a thigh in an internal rotation.

Piriformis Paradox

A piriformis muscle perform external hip rotation when the angle of hip flexion is less than 60 degrees. When the angle of hip flexion is more than 60 degrees it performs internal rotation.

Piriformis Action Video

This is well demonstrated in this video.

So, in pigeon pose we have a hip flexed and that is why one has to stretch piriformis by positioning it in external rotaion.

This paradox explains why one can use 2 different type of stretches for piriformis.

Piriformis: Stretch Method 1

All variants of external rotation. "Pigeon pose" type.

Piriformis: Stretch Method 2

Just the opposite. All variants of internal rotation. "Manual therapist" type.