Yoga Anatomy

60   Yoga anatomY

Agonist and antagonist roles are relative, and they change as the focal joint and the

joint action change. These terms do not describe an absolute quality inherent in the muscle

itself but something about its relationship to another muscle during a specific moment at

a particular joint. Whether a muscle is an antagonist or an agonist depends on which joint

and which joint action are the points of focus and where the main resistance to the move-

ment is found (figure 4.5).

The muscles that support and modulate the action of the agonist or antagonist muscles

are called synergistic muscles. The synergistic muscles also act to minimize excess move-

ment at a joint or to stabilize one part of the body to support movement in another part.

When synergists act to stabilize in this way, they are also called fixators. Alternatively, the

term synergistic is used to describe a whole group

of muscles that work together to create an action.

Synergistic muscles are essential for maintaining

balanced joint space and for the health of the joint.

Organizing muscles into agonist–antagonist pairs

is very useful when looking at a specific action at a

single focal joint. In order to consider how different

joints relate to each other, it is important to examine

other kinds of relationships between muscles.

one-Joint and Multi-Joint

Muscles^2

Muscle groups and individual muscles have layers.

In the limbs the deepest layers are closest to the

bones and the superficial layers are closer to the

skin. In the torso, however, some of the deepest

layers of muscle are deeper than the bones, and

they are closest to the thoracic, abdominal, or pelvic

cavities and organs.

Different muscles can cross different numbers of

joints. Some can cross one joint, and some can cross

two joints; some muscles in the hands and feet cross

8 or 9 joints, and some muscles in the spine cross

Sometimes, even in a simple
movement, the antagonist for
the first part of the movement
becomes the agonist in the
second part of the movement.
For example, when the arm is
extended out to the side, paral-
lel to the floor, and the elbow is
flexed so that the hand moves
toward the shoulder, in the first
part of the movement (bringing
the forearm perpendicular to the
floor), the triceps brachii is an
antagonist to the action of the
biceps brachii. In the second part
of the movement (bringing the
forearm from perpendicular to the
shoulder), the triceps brachii is the
agonist, acting eccentrically.

E5267/Kaminoff/fig4.5/421801/alw/pulled-r2

Biceps brachii

Triceps

brachii

Figure 4.5 When the focal joint is the elbow and the joint action is flexion against gravity, the

biceps brachii is the agonist and the triceps brachii is the antagonist.

(^2) While the terms one-joint and multi-joint are not used exclusively by Body–Mind Centering (BMC), the approach to
muscular repatterning in BMC is the most sophisticated use of these concepts that I have encountered.