Yoga Anatomy

Notes

Extensors of the spine are lengthening and active. As the pose deepens, the spine flattens
to the floor and moves toward axial extension.
There is a strong action of nutation at the SI joints, as the top of the sacrum nods forward
while leaving the iliac bones behind. If the sitz bones release from the floor, the action is
more in the hip joints and back of the legs. If the sitz bones stay grounded, the action is
distributed more evenly between the legs and spine.
The starting position of the legs is sometimes described as external rotation. If the feet
point up to the ceiling, there is no external rotation in the hip joints. There is instead flexion
and adduction at the hip joints.
If the legs roll inward, there can be too much lengthening for the inner knees and
adductors. For tight students, it is preferable to bend the knees a bit (with support) so that
the stretching sensations are felt more in the bellies of the relevant muscles. Sensations of
stretch occurring near the joints and muscle attachments are indicators that nothing useful
is likely to result from the movement.

Breathing

The act of gradually lengthening the spine in this pose can be greatly assisted by the breath.
The exhalation, if initiated in the lower abdomen, can help anchor the sitting bones and
ground the backs of the thighs, whereas the inhalation, if it’s initiated in the upper chest,
can help to lengthen the spine. In short, the exhalation can ground the posture’s lower
half, and the inhalation can lengthen the posture’s upper half.

Skeletal joint actions

Spine Lower limbs

Mild flexion moving toward axial extensionSI joint nutation, hip abduction and flexion,

knee extension, ankle dorsiflexion

Muscular joint actions

Spine

Eccentric contraction

To distribute flexion through length of spine:

Spinal extensors

Lower limbs

Eccentric contraction Passively lengthening

To abduct leg while folding forward in

hip joint:

Gluteus medius and minimus, piriformis,

superior and inferior gemellus, obturator

internus

To modulate forward bend:

Semitendinosus, semimembranosus

(medial hamstrings)

Gracilis