Physiological principles of sotai ho. Painless treatment of musculoskeletal problems.

3. There are over 215 pairs of skeletal muscles in the human body.
Almost all body movement, such as walking or holding things,
and every conscious physical action such as speaking, is
caused by skeletal muscle contraction.
Skeletal muscle is the only type of muscle which is under voluntary
control, which means a person consciously controls its movements.
Together, they make up about 40% of the body’s weight.
Muscles produce movement, are essential to maintain posture and
generate heat. This heat is vital for maintaining normal body
temperature.

4. Skeletal muscles are made up of many long fibers, bundled
together, and surrounded by a sheath called the epimysium.
Most muscles are attached to bones by tendons.
Fascia is the connective tissue outside the epimysium which
surrounds and separates muscles.
The epimysium gives the muscle its shape and provides a
surface against which the surrounding muscles can move.
Movement is caused when skeletal muscles contract and pull the
tendon, which in turn, causes the bones to move at the joints.

5. Muscles are grouped together in pairs.
To straighten the arm, you need to do the opposite action, to
contract the triceps and relax the biceps.
When you bend your elbow, your biceps brachii muscle contracts
and the triceps brachii relaxes.
Skeletal muscles only pull in one direction. When one muscle
of a pair contracts, the other relaxes.

6. The muscle that contracts is called the prime mover or agonist
Prime movers are helped by other muscles called synergists
or stabilisers.
The muscle that relaxes is called the antagonist. In this case, the
triceps is the antagonist muscle.
In our example, when we bend the elbow, the biceps brachii is
the main agonist muscle.
The brachioradialis assists the biceps to flex the elbow.

8. When a muscle is stretched, so are the muscle spindles. These
send signals to the spinal cord and a reflex occurs which
causes the muscle to contract.
The stretch or myotatic reflex is a process that causes a contraction
of the muscle, thereby stopping a stretch.
Skeletal muscles contain sensory receptors called muscle
spindles, which detect changes in the length of tissue.
The stretch reflex is a protective mechanism to prevent
overstretching and muscle fiber damage.
The Stretch Reflex
A major role of the myotatic reflex is the maintenance of
posture.

9. When a muscle is contracted too hard, the GTO registers the
increasing tension in the tendon, and a reflex occurs which
causes the muscle to relax.
Autogenic inhibition is a process that causes the lengthening or
relaxation of the muscle.
The tendons of skeletal muscles contain another type of
sensory receptors called Golgi tendon organs (GTO), which
are sensitive to muscle tension.
Autogenic inhibition is a protective mechanism to prevent the
tearing of muscles.
Autogenic Inhibition

11. Muscle pain and spasms are spontaneous muscle contractions
which cause muscle shortening.
Pain is more intense when stretching the shortened muscles.
When the muscles shorten, the bones are held together more tightly
than normal. This constriction, can cause pain and limit the range of
motion or flexibility.
Muscle shortening produces pain by pulling on tendons.
Shortening causes an imbalance between agonist and antagonist
muscles. Because the agonist muscle is shortened, the antagonist
muscle is overstretched.
Muscle shortening increases wear and tear and contributes to
degenerative changes such as tendonitis, bursitis and
osteoarthritis.

12. In sotai the movement is in the direction that does not cause
pain.
Since we push those movements to the limit - without pain, the
stretch and autogenic inhibition reflexes act.
So, instead, what the exercise does, is to contract further the
shortened muscle, and to stretch the overstretched muscle.
This means that we do not try to stretch or lengthen the
contracted or shortened muscles, because it would be painful.
The stretch reflex acts on the shortened muscle, and autogenic
inhibition acts on the overstretched muscle.

13. Nerve impulses will be sent to the agonist muscle
(which is shortened), to stretch, and to the antagonist muscle
(which is overstretched), to contract.
We have increased the range of motion of the movement.
The shortened muscle has lengthened. The overstretched muscle
has shortened.
So we have achieved our aims without any pain.
The movement can be done now with less pain. We have
effectively reduced the pain.
The muscles are more balanced.