Fascia, Collagen, Motion, and Bodywork

It is common to visualize our own bodies in a static manner “my quads are here”, or “these two muscles run next to each other.”  But we are in constant motion and our muscles and fascial surfaces are constantly sliding and shifting around each other as we change how we are holding our bodies. Every muscle is responsible for certain lines of force and tension, and as we move and change our shape we shorten some lines and lengthen others.  Ideally all the surfaces are free to move and we can achieve our desired motion with minimal effort, but this is rarely the case.

The body is constantly laying down new collagen fibers which add stiffness to our structure.  One way of thinking about this is as an energy saving adaptive process of the body. If an area of the body does not need to move much, instead of holding the associated muscle at a constant tension, the body can stiffen up the structure there so the muscle doesn’t have to work so hard. This is analogous to how a plant or tree stiffens up its primary truck, allowing it to get woody and strong to support the load.

The following video is an excellent, (and fun!) introduction to this issue.  You will get to see the collagen fibers — what he calls “the fuzz” on actual cadavers and see how it affects motion.

What I take away from this video is an answer to the question “how does your body know where to add collagen to stiffen up a muscle?” The answer is that it doesn’t “know” where to add collagen, rather you are constantly producing collagen along all the muscles and fascia.  Anywhere that you are actively using and moving your muscles will stay loose and free to move, but areas that are being held stationary will continue to stiffen up.  In other words, your body doesn’t have an intentional response, but it naturally reinforces whatever daily patterns of use that you are engaged in. This makes me want to jump out of my chair and move my body!

Another question worth asking from this is: “If muscles are fuzzed up and cannot slide freely, what happens?”  Besides limiting your range of motion, adhered (i.e. stuck together) muscles are a major source of joint pain.  Imagine two muscles that cross each other at some angle — if they are glued together then when you pull on one, you end up pulling on the other.  This causes forces to distribute through your body in inappropriate ways.  Often the result is that the joints get pulled out of their optimal alignment and instead of passing forces across the joint cleanly the forces pass into small muscles or tendons which were not designed to take that sort of load.  Those muscles will become strained and locked tight, often stiffening up and causing issues to cascade further through the body.  As the body tightens up, joints are pulled tight, causing bones and ligaments to rub and other forms of internal irritation and damage.

Since our body is a single complex web of tension (see “Introduction to Biotensegrity”), changing the tension structure locally (i.e. across a muscle or two), can have a cascading impact on the entire structure. This leads to the common problem that an adhesion (“fuzz”) in one part of the body results in pain in a joint somewhere else.  An example would be having an injury in your calf that tightens up the network locally such that the hamstring is also pulled tight, which results in lower back pain.

So, stretching and using our bodies will keep our body adapting for motion! If you spend most of your day sitting in a chair or a car, you should think about how much daily motion muscles in your back and hips are getting. This is critical if you still want to be dancing and running around joyfully when you are 80 years old! (I know I would like to! <grin>)  But what do you do if you already have scar tissue or other adhesions (from under-used muscles, etc) that prevent you from moving freely now?  If the adhesion is thick enough, you will not be able to loosen it just through stretching and motion. That is where bodywork, such as massage or other physical techniques, comes in.

A great book for learning more about the fascia, and the global network of how forces flow through it is Anatomy Trains: Myofascial Meridians for Manual and Movement Therapists. Tom Myers has been doing dissections with fresh cadavers, which allows him to extract long chains of fascia before it hardens. Traditional dissection techniques with preserved cadavers cause the various layers of fascia to harden and glue together, which makes it very difficult to understand the functional structures of the body.

UPDATE To see some of my recent work on applying fascia centric concepts to robotics, see my post on a robotic tensegrity snake, and a video of a lecture I gave in Switzerland.