One of the unique facets of our field (and granted there are many) is that much of our education follows the model of oral tradition. In an oral tradition, information is passed down from teacher to student and assumed to be valid and accurate because “that’s what our former teachers taught, or that’s what the guru that first started this taught.” Other disciplines such as yoga or martial arts also rely strongly on oral tradition for transmission of the teachings.
Oral traditions can work well, but this education model doesn’t work in a health care approach to massage therapy where information is continually updated as our research base grows. In many cases we have to un-learn things that we previously thought were true because now we have developed a better understanding through research and analysis.
Some of the thought leaders that started various “systems” and techniques in massage developed their ideas based on what was current understanding of physics and physiology at the time. Others developed their approach based on ideas that weren’t grounded in science but had some other appeal, such as an attractive esoteric theory.
The blending of our oral tradition teaching and our new scientific understanding makes this an interesting time to be in the expanding field of massage therapy. However, it is also quite challenging because the oral tradition principles may clash with current scientific understanding. This clash often leads to vigorous debates. I think academic debate is a good thing. Unfortunately, much of this debate process is carried out on social media forums and quickly devolves into name-calling, derision, tribalism, and personal attacks. I would like to see more constructive academic discussion, so I offer this post in that spirit.
The various techniques falling under the umbrella of ‘fascial manipulation’ – myofascial release, structural integration and all of its derivatives– are at the center of oral tradition confronting evolving scientific understanding. In this post I want to look at one of the critical concepts of fascial manipulation that runs counter to what we now know about tissue physiology.
A number of the primary fascial manipulation techniques suggest that through the application of manual force, we are elongating the fascia and thereby changing structure, posture, or the body’s functional movement capacity. However, this idea directly contradicts what we know of the physiological properties of human connective tissues, so the model has some fundamental flaws.
Connective tissues have specific biomechanical properties. When force is applied to a tissue, the tissue responds by deforming in response to the force’s magnitude, direction, and line of application. For this analysis we assume the amount of force applied is within therapeutic parameters and not enough to damage the tissues. The tissues deform in one of two ways: elastic deformation or plastic deformation. Elastic deformation occurs with smaller force loads. In elastic deformation, a tissue deforms slightly when a load is applied and then immediately recoils to the original state when the force load is removed.
Plastic deformation occurs when the force load is more significant. The higher force load is strong enough to deform the tissue beyond its normal response. Once the force load is removed, the tissue does not return to its original state because the force is sufficient to change the shape properties of the tissue.
You can demonstrate elastic and plastic deformation with a small metal rod like a coat hanger. If you apply a small amount of force with your fingers in the middle of the long expanse of the coat hanger, it will return to its original shape when you remove the force. That is elastic deformation. If you apply a greater force, the metal will permanently change shape even after you remove the force. That is plastic deformation.
Fascial tissue extends throughout the body, and its ubiquitous presence is one of the key ideas advocated by practitioners of fascial manipulation. The idea is that fascial tissue plays a prominent role in giving our bodies shape and structural integrity. Fascial tissue also has to be highly elastic. Otherwise all kinds of forces applied to our bodies during the day would permanently deform our fascial tissues.
If we are changing structural shapes with fascial manipulation techniques that means we are applying enough force in our treatments to cause plastic deformation. Research has shown that the amount of force required to cause plastic deformation of fascial tissue goes well beyond what a practitioner applies in manual therapy treatment. Consequently, it is unlikely that we are significantly molding or changing the shape of fascial tissues with our manual therapy.
“But my clients get great results and feel so much better, and I can feel the tissues soften when I work, so this must be working!” That is often the argument presented to defend the idea of fascial manipulation. Anyone who has spent any time in a clinical environment performing manual therapy can attest to these types of changes that they feel and also hail the client’s experience of improved sense of movement or perhaps posture change. But that doesn’t mean we are elongating their fascia. It is entirely feasible, and most likely that other physiological processes (most likely neurological) are behind most of what our clients are experiencing. We will explore potential explanations for these results in future posts.