In Myofascial Release Part 1 I reviewed in general the structure and function of the connective tissue that surrounds the muscles, which is the target structure of myofascial release. Now that we have a basic understanding of what the fascia is and what it does, let’s review some of the issues that myofascial release is meant to alleviate.
First of all, I would like to offer clarification on a statement I made in Part I regarding the innervation and circulation supplied to myofascia. I said that “While fascia does not contract on its own the way muscles do, or have direct connection with the circulatory system…”. I realize this implies that fascia does not contract or have circulation at all, and this is not the case. Researchers found that within the collagen fibers of fascial tissue are embedded smooth muscle cells and capillary systems. Smooth muscle fibers are those found in our internal organs that we do not voluntarily control, such as the stomach and intestines. As a result of the existence of these muscle fibers, when connective tissue was subjected to prolonged stretch, the tension of the tissue increased, indicating “contraction” of the fascia. These studies show that fascia is an active rather than passive tissue, as previously thought, and it can be extremely responsive to forces on the body, whether due to muscle contraction or stretch.
The painful areas usually targeted through myofascial release are called trigger points. When using the foam roller these spots are typically easy to find. As you roll the pressure often feels like strong massage, and when pressure is applied on or near the trigger points it is usually quite painful. The goal is to “release” these trigger points to alleviate the pain and improve function of the area. But what causes these trigger points and the pain associated with them?
Although fascia may not have large vessels directly supplying flow of blood or fluid, there are many points in the fascia where an artery, vein and nerve traveling together pass through, or perforate, the fascia. It was found that the majority of the 361 Chinese acupuncture points corresponded with one of these perforation points. Patients experiencing pain at these sites showed additional collagen buildup around the perforation described as “strangling” the vessels and nerves. This collagen buildup and subsequent pain is what is creates these trigger points.
In addition to the physical buildup of collagen associated with trigger points, there are also chemical differences. A study measuring the concentrations of a variety of chemical markers associated with pain and inflammation (inflammatory mediators, catecholamines, neuropeptides, cytokines) took samples from trigger point areas in the trapezius muscle (upper back) and unaffected gastrocmenius (calf) muscles. These chemical markers specifically indicate a decrease in fluid circulation, decreased ability to utilize oxygen and increased acidity. The increase in acidity also inhibits acetylcholinesterase activity at the motor end plate. This means that after the muscle fiber is stimulated to contract, the chemical that subsequently allows the muscle to relax is not able to function properly, causing the muscle to stay in a state of partial contraction. The results of these things are increased metabolic demand, muscle fiber shortening and muscle tension. It is easy to see how with these things occurring, muscle function would be affected along with the pain associated with trigger points.
This study also found that many of these biochemical markers were elevated in the trigger point areas as well as in unaffected muscles when compared to subjects with no trigger points. This indicates that the inflammation that occurs in areas of pain can affect the chemical balance of the fascia system of the entire body. There is debate whether the increased inflammation markers are the cause or effect of trigger points and more research is needed to determine this.
Now we have a better idea what is happening physically and chemically at the trigger point sites. Based on what we know so far, I think it is fair to say that in addition to just feeling better after doing myofascial release, there is probably some measurable physical and chemical improvement to the muscles. As with any therapy or training technique, there are questions about when and for how long we should perform foam rolling and other SMR techniques in order to increase performance rather than decrease it. Keep reading, as I will address this next!
Schleip, R. Fascial plasticity-a new neurobiological explanation: Part 2. Journal of Bodywork and Movement Therapies, 2003. 7(1) 11-19.
Shah, J.P., Danoff, J.V., Desai, M.J., et al. Biochemicals Associated With Pain and Inflammation are Elevated in Sites Near to and Remote From Active Myofascial Trigger Points. Arch Phys Med Rehabil, Vol 89, January 2008.