The muscles of the body are interconnected through connective tissue or fascia (fibrous membrane that surrounds and relates them); in this way the muscle chains are created.

These chains facilitate the redistribution of forces throughout the body, and allow the muscles not to act in isolation, since if they did, they would not be effective or capable of performing different functions, movements, or maintaining a posture.

We come "programmed" with movement and postural control patterns designed to maintain our balance, save our energy expenditure (thus being more efficient) and stay within a comfort zone (avoiding pain).

There are several factors that can upset this balance:

- Bad postures maintained over time.

- Bad gestures that are performed repeatedly (specific movements).

- Sedentary lifestyle or excessive activity.

- Bad nutrition.

We will give an example of how tension in a muscle chain can influence pain in the left knee:

There is a crossed muscular chain that connects the thorax on the right side (the liver area) with the pelvis on the left side.

When the liver is in dysfunction, that is to say that its connective tissue that surrounds it is in tension, a destabilizing force is transmitted through the left crossed muscular chain, generating an influence on the left lower limb.

Releasing the liver, mobility in the left knee improves, also achieving a balance in the discharge of weight on the lower limbs.

For this reason, it is important to keep in mind the concept of the globality of the body, not only evaluating the area of the symptom.