The Psoas Muscle and Eccentric Contraction

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Connecting the Body
If a group of people are all talking to each other and collaborating then the organisation can be relaxed because the group can adapt to change by communication. On the other hand, if the people in the group are not communicating then the group may need someone to tell everyone what to do and to tightly control the group behaviour.

The same is true with the body. If each part is communicating and collaborating then the muscular system can relax and only use muscles when they are necessary for movement or temporary bracing. On the other hand, if the parts don’t sense each other then the nervous system tends to hold everything together tightly to keep control.

Chronically tense muscles tend to decrease the sense of connectedness between body parts because those parts are held still and immobility decreases sensation.

But this is also true of ‘collapsed’ muscles.

Toned Antagonists
The sensation of connection is optimised when a muscle is toned but not tense and, in particular, when it is toned while it is lengthening. Muscles need to be able to let go of full-on contraction to allow the opposite movement to take place. So a muscle that flexes a joint needs to let go to allow for extension. In this role it is called an antagonist (which is an unfortunate name because it implies conflict)

But if the antagonist simply collapses then the action of the active muscles (called the agonists) is jerky, violent and harsh. On the other hand if the antagonist is toned and elastic while it is lengthening then it does three useful things:

  1. It smooths the movement like suspension on a car smooths the bumps
  2. It guides the movement creating grace and efficiency
  3. Most importantly, the elasticity pulls on the bone at the origin of the muscle and moves it slightly, thus creating a sensation of connection between the two bones.

Chains of Connection
The third effect of toned lengthening moves the bone at the origin of the muscle and, then another muscle has to lengthen to allow this secondary movement. If this letter muscle is also toned it pulls on yet another bone and, as you can see, a chain of connectivity can be felt through the whole body.

You can see these pathways of connection most clearly in athletes and dancers. When they perform a strong movement, their whole body is involved.

Roger Federer is a good example of an athlete whose muscles lengthen with elastic tone. this makes his movements graceful as well as powerful and he tends to avoid injury. See how the extension of his right arm spirals through his whole body into his right foot.
Rafael Nadal tends to emphasise the contracting muscles rather than the tone of the lengthening muscles. His tennis is just as good as Federer’s , and his play is full of energy and excitement, but maybe his style of movement makes him more vulnerable to injury.

The Psoas Muscle
In this lesson we will use the Psoas muscle as an example.

If the Psoas muscle is toned when lengthening then it guides force from the leg smoothly into the spine. It also elastically binds the legs to the torso and plays a major part in the sensation of body integration.

Another role of the toned psoas is to support the lumbar spine. With the posterior spinal muscles, the psoas muscles buttress the lumbar spine, providing soft and flexible support for a part of the body that is not braced by other bones.

Creating TONE can release chronic TENSION
Most often physical therapists talk about tight Psoas muscles and give exercises and stretches to loosen it.

However, many deep muscles like the psoas are tight because they are compensating for a lack of connectivity in the fascial-muscular system.

One of the general principles that I follow is that, instead of trying to release chronic tension, I help the body to feel connected. When this happens, the tight control is no longer necessary so the chronic tension can release. One of the best techniques for helping the body to feel connected is to teach muscles to have tone while lengthening.

The following video shows how to help a muscle to learn how to lengthen with tone. The technique can be used in almost every muscle, although there are some deep muscles that are difficult to sense for a normal person. We show how to use these techniques with the Psoas muscle.