Yoga Anatomy

Muscular joint actions

Spine

Alternating concentric
and eccentric contractionsConcentric contraction Eccentric contraction

To maintain neutral align-
ment of spine:
Spinal extensors and flexors

To rotate spine toward front

leg:

Erector spinae, internal oblique

(front leg side); transverso-

spinalis, rotatores, external

oblique (back leg side)

To balance rotation around

axis:

Transversospinalis, rotatores,

external oblique (front leg

side); erector spinae, inter-

nal oblique (back leg side)

Upper limbs

Concentric contraction

To abduct scapula:
Serratus anterior

To stabilize and abduct shoulder joint:

Rotator cuff, biceps brachii (long head),

deltoid

Lower limbs

Front leg Back leg

Concentric
contraction

Eccentric

contraction

Concentric

contraction

Eccentric

contraction

Passively

lengthening

To extend knee:
Articularis genu,
vastii

To allow hip

flexion:

Hamstrings at

hip joint, glu-

teus maximus

To level and

center pelvis

over feet and

to maintain

balance side

to side:

Gluteus medius

and minimus,

piriformis,

superior

and inferior

gemellus,

intrinsic and

extrinsic mus-

cles of foot

To extend knee:

Articularis genu,

vastii

To maintain

arches of

foot without

inhibiting

dorsiflexion

of ankle:

Intrinsic muscles

of foot

To allow hip

flexion with-

out dropping

back leg

forward:

Hamstrings at

hip joint, glu-

teus medius

(posterior

fibers), adduc-

tor magnus,

gluteus maxi-

mus

To allow outer

ankle to

lengthen

without col-

lapsing inner

knee or inner

foot:

Peroneals

Soleus, gastroc-

nemius

(continued)