Yoga Anatomy

Muscular joint actions

Spine

Concentric contraction Eccentric contraction

To extend spine:

Spinal extensors

To prevent hyperextension at lumbar spine:

Psoas minor, abdominal muscles

Upper limbs

Concentric contraction Passively lengthening

To abduct, upwardly rotate, and elevate

scapula:

Serratus anterior, upper trapezius

To stabilize, flex, and adduct shoulder joint:

Rotator cuff, coracobrachialis, pectoralis major

(upper fibers), anterior deltoid, biceps bra-

chii (short head)

To rotate forearm and grasp foot:

Supinator and flexors of hand and fingers

Rhomboids, latissimus dorsi, pectoralis major

(lower fibers), pectoralis minor

Lower limbs

Standing leg Lifted leg

Concentric

contraction

Eccentric

contraction

Concentric

contraction

Passively

lengthening

To keep knee in neu-

tral extension and

balance on single

leg:

Articularis genu,

quadriceps, ham-

strings; intrinsic and

extrinsic muscles of

foot and lower leg

To allow lateral shift:

Gluteus medius and

minimus, pirifor-

mis, obturator

internus, superior

and inferior gemel-

lus, tensor fasciae

latae

To allow anterior tilt

of pelvis without

falling forward:

Hamstrings, gluteus

maximus

To create hip exten-

sion and knee

flexion to enter

pose:

Hamstrings

To create hip exten-

sion, internal

rotation, and

adduction:

Adductor magnus

To create hip exten-

sion:

Gluteus maximus

To extend knee

and increase hip

extension against

resistance of hand

grasping foot:

Vastii

Iliacus, psoas major,

rectus femoris

Natarajasana (continued)