SaveYourself.ca • Sensible advice for aches, pains & injuries
Sheets of fascia can contract a bit like muscle … but how strongly? Enough to make a difference?
published 10/16/11
Does fascia — sheets of connective tissue — have any properties that are relevant to healing and therapy? Are there compelling reasons to do therapy that is “aimed” at fascia? In the summer of 2011, I wrote about a pattern of flawed clinical reasoning about fascia — that article was popular and controversial.1 Many therapists seem to have excessive enthusiasm about fascia, often based on painfully vague oversimplifications about why it matters. They often emphasize biomechanical factors as a major cause of pain — a largely obsolete therapy paradigm. Despite a huge industry and culture of fascia-inspired treatment methods and conferences, it is not clear that fascia should be a “tissue of interest.”
I have challenged my readers to provide me with examples of science that show that fascia has properties that are relevant to therapy and healing. Only a handful have done so, and the two examples I’ve written about so far have done nothing to impress me with fascia’s clinical importance. The first was just a weak sauce.2 The second paper I analyzed led me in exactly the opposite direction, because it concluded that even thin fascia is so tough that it is basically inconceivable that it could be physically changed (stretched, loosened) without vice grips.3
In this article, I take a careful look at a third example of fascia science, suggested to me in an email by Dr. Gil Hedley. I criticized Dr. Hedley in my original article on this topic in August, 2011, and he was understandably a bit irritated. Nevertheless, we had a short, civil discussion about the subject matter. Since he clearly believed me to be ignorant of fascia science and in dire need of educating, I asked him to recommend some reading to me — a favourite paper showing something interesting and clinically relevant about fascia. As expected, he recommended a paper I was already familiar with, because it is something of a classic of fascia science: Robert Schleip’s 2006 dissertation on the contractile properties of fascia.
“Fascia is able to contract in a smooth muscle-like manner and thereby influence musculoskeletal mechanics”
Schleip et al. Proceedings of the 5th World Congress of Biomechanics, Munich. Volume , Number , p51-54. 2006.
Schleip and colleagues convincingly showed that fascia contains muscle cells and that they can contract. That is undeniably interesting as physiology, but we must ask: “Does it even matter whether its right or wrong?”4 Is it clinically relevant?
Before we get to clinical relevance, I’ll quickly explain what Schleip et al. found: a kind of muscle cell in rat fascia, which they described as “rather unexpected.”5 They also tried out various methods of stimulating them in vitro (test tube) and found that, by golly, those muscle cells did what muscle cells do: they contracted! Slow, weak contractions. But they contracted.
It’s certainly not difficult research to understand.
Bear in mind that, for a long time, fascia was and often still is thought of as a fairly lifeless, inert substance, the Saran Wrap of biology. I still hear various educated people referring to it in this way. However, massage therapists and chiropractors (in particular) are prone to swinging to the opposite extreme and talking about fascia as though it is more interesting than a lifetime subscription to National Geographic. The truth is somewhere in the middle.6
We are not talking about a lot of muscle cells here. If you had blueberries with your cereal in the same proportion, you’d be disappointed — not enough blueberries. It’s just a few muscle cells scattered throughout the fascia, visible only when you look very closely and in just the right way.
By any measure, fascial contractions are dramatically less powerful than muscular contractions. If anything, this diagram gives far too much credit to the power of fascia, which would barely register at all if depicted more accurately.
Nor are we talking about particularly strong contractions. Fascia isn’t going to be ripping apart any chains with its bare hands. The maximum force generated by a small bundle of contractile rat fascia was around 35mN.7 In plain English that’s “not very dang much” or the somewhat more precise “about what it takes to set an AA battery rolling on a nice smooth surface.” Not bad for a bundle of rat fascia, perhaps, but it doesn’t really hold a candle to middle-of-the-night charlie horses either.
Compared to the power of muscle contraction, fascia power barely even registers.
Schleip et al.’s basic finding seems sound enough, and I see no reason at this time to dispute the observation that fascia can contract. If there’s anything wrong with their research methods, I don’t know what it is. But for the property they described to matter to therapists who are choosing to focus their therapeutic attention on fascia — for any biological property to be clinically relevant — it must be significant enough to have an effect on health. (It then must also be something that we can do something about, but let’s start with it mattering in the first place.)
Schleip et al. characterized the raw power of fascial contraction rather differently than I just did. I deliberately made it sound trivial, within the bounds of their numbers.8 In their words, however, in the large sheets of fascia in the low back, the contraction could be “strong enough to influence low back stability and other aspects of human biomechanics.”
Stability? Really? Even if you wildly exaggerate their numbers, it would still only account for a fraction of a fraction of the postural muscle power involved in dynamic spinal stabilization, never mind the generally mind-blowing structural toughness and resilience of the human spine. The idea that low back stability could be affected in any way by such a small force is hyperbole by orders of magnitude.910
And that’s based on an estimate of the theoretical maximum force generated by the biggest and thickest blankets of fascia in human anatomy. In most places in the body, fascia is much less substantial — tough for its weight, but mostly quite thin and wispy, and a lot of it even microscopic.11 The forces generated must be dwarfed by that of muscle itself — in rough proportion to the number and size of contractile cells involved.
That fascial contractions might influence “other aspects of human biomechanics” is a vague statement, to say the least. A general example of such “aspects” might be that contracting fascia could be involved in biomechanical asymmetries — tighter on one side than the other. The validity of such a concern depends on just how sensitive you think human biomechanics are to forces so subtle that no one really had any idea that fascia contraction was even happening before this study. As regular readers here will know, I think biomechanics are strongly over-rated as a factor in all kinds of pain problems, and there’s extensive evidence that human beings are wonderfully adaptable and cope surprisingly well even with gross deformities. I make that case in great detail in another article,12 and I have been steadily losing patience over the years with all suggestions that subtle biomechanical force or asymmetries matter much.
The wording of the conclusions of Schleip et al.’s paper is synonymous with saying that fascial contraction is relevant only if structuralism is a useful mode for doing and thinking about therapy. Worse, their phrasing betrays a strong bias in favour of the “importance” of fascia — and a fine demonstration of a “pattern of flawed clinical reasoning” about fascia. Almost inevitably, it turns out the study was funded by the International Society of Biomechanics, the Rolf Institute of Structural Integration, and the European Rolfing Association.13
Weak fascial contractions strike me as being scientifically fascinating but clinically boring. Once again, far from making me interested in fascia as a target for therapy, fascia science is convincing me of just the opposite.
If it makes anyone feel better about all this, I’m happy to concede that fascial contractility might be a little bit clinically relevant. Other evidence might even reveal something important — although that would surprise me. It doesn’t hurt my main point to make these concessions. To make my point, all I have to establish is that the clinical relevance is debatable, dubious, and probably minor at best, rather than the slam dunk it needs to support even half of the “excitement” about fascia you see in the therapy industry today.14
In his original dissertation, Schleip limited his speculation about clinical implications to the broad generalization that it can “influence musculoskeletal mechanics,” such as spinal stability. In a follow-up paper for Medical Hypotheses,15 he and several colleagues generally suggest that fascial contractility is a factor in muscle stiffness. The high water mark for potential clinical relevance is spelled out in this passage:
This offers the possibility of a new understanding for many pathologies that involve a chronically increased myofascial tonus. Examples include conditions such as torticollis, low back pain associated with paraspinal compartment syndrome, tension headaches, and others. Similarly a decreased fascial tone could be a contributing factor in conditions that are often associated with decreased myofascial tension, such as in back pain due to segmental spinal instability, peripartum pelvic pain, or fibromyalgia. While usually other factors play a major role as well in these pathologies, it is possible that their progress could be influenced additionally by the regulation of fascial tissue tone …
The emphasized phrase is problematic. It’s a rather drastic understatement. For instance, other factors don’t “usually” play a major role in those conditions, they always do — unless Schleip et al. mean to suggest that fascial contraction is ever their main cause? And the role of those factors isn’t just “major,” but nearly total — relative to the presumably minor contribution of fascial tension. Indeed, it “could be” a minor contributing factor, but no one actually knows that, and some of the items listed go particularly far out into left field. I’ve already mentioned how hyperbolic it is to suggest that fascia could have any impact on spinal stability. Another weird item here is fibromyalgia, a fascinating condition that might conceivably be affected in some small way by fascial contraction, but which is overwhelmingly a nasty disease of the nervous system. Lobbing it out there as a main example16 of how fascial contraction might matter makes about as much sense to me as saying that people with cancer might have some contracted fascia; perhaps they do, but who cares?
The most interesting item listed is “compartment syndrome,” which is decidedly not a common complication or cause of back pain, but certainly is a problem (especially in the shins).17 Compartment syndrome is excessive pressure in a fascial compartment, like a sausage swollen in its wrapping. If fascia were to start squeezing a compartment for some reason, it might be a problem. It is the one item listed where there is a clear, direct and logical connection between “fascia can contract” and a way that it could contribute significantly to a health problem. That is clinical relevance. And yet there is still a clear problem with the scale here. Compartment syndrome is by definition only a problem when the pressure is significant, probably exceeding the maximum force with which fascia could squeeze the compartment. I don’t know, of course — it would be an interesting research project — but it does seem like, again, fascial contraction is probably not strong enough to matter. Still, at least it’s easy to see how it could matter in principle, and the numbers might favour fascial contraction as factor.
So you see how this goes: for one candidate example after another, the clinical relevance of fascial contraction is dubious or minor.
One of the lower moments in biology history was the labelling of non-coding DNA as “junk DNA” in 1972. The first time anyone with a scrap of imagination heard that, they thought, “Yeah, right.” As biologists slowly figured out what all that “junk” is for,18 there was a lot of “Well, yeah, okay, that’s more like it. Of course.” It’s interesting science, but in some ways those discoveries are still overshadowed by the way we’re all not so very surprised.
Similarly, the presence of muscle cells in fascia is no shocker. I never believed fascia was entirely inert any more than I believed in the junkiness of any DNA. If you spend much time studying biology, it quickly becomes apparent that there are no sharp lines or divisions, and that we consist of an incomprehensibly diverse and interconnected community of cells. That connective tissue has a small population of muscle cells strikes me as blindingly unsurprising. Muscle blends exquisitely into tendon, with no clear demarcation at the cellular level: at the microscopic level, it’s like walking through the overlapping zone of two heavily integrated adjacent neighbourhoods, and the further you go away from the muscle, the fewer muscle cells you see, and the more fibroblasts and their fibres. That connective tissue has a small population of muscle cells strikes me as blindingly unsurprising. Fascia surrounds and fractally wraps every muscle inside and out, for crying out loud — how could it not have a few muscle cells and overlapping properties?
I didn’t know that before it was confirmed, but I certainly don’t find it particularly surprising. I suspect that the slightly contractile properties of fascia are simply at one end of a continuum of motor function. Our muscular system is overwhelmingly our primary means of reacting to stimuli — the major output of our nervous systems — and in general terms the slight contractility of fascia is probably just the fringes of that functionality, a little bit more of the same. There are probably some subtle differences, but they are subtle and arcane and ultimately just a slight variation on the biological theme of muscularity. I’m not saying it’s completely uninteresting, but it’s overshadowed by the much more interesting muscular system as a whole, about which fascia is simply a mildly intriguing subtopic. And, in terms of clinical relevance, the muscular system itself is in turn overshadowed by neurology.
I would never normally have beeen interested in this paper — I don’t think it’s good enough science. I spent time on it only as a gesture of good faith to a critic, who suggested it as an example of basic fascia science that matters. It may not have been a good choice for that purpose. It is a test tube study showing that naked cells handled stress better (fewer signs of harm) if they were treated with, believe it or not, “simulated” myofascial release (MFR). A meaningful, accurate simulation of manual therapy on naked cells is an amusing notion, and it’s clear that what happened to those cells differs dramatically from what would happen in a real living body.
Comments: In this paper, Chaudhry and colleagues show that fascia is much too tough a tissue to “release” by mechanical deformation. This contradicts a defining rationale for therapies focussed on manipulating fascia. Although not all therapists assume that fascia is “tight” and needs to be “released,” a great many still do.
BACK TO TEXTIn fact, on one occasion, a rather pedantic experimental psychologist was telling him about a long, complicated experiment he had done, incorporating all the proper controls and using considerable technical virtuosity. When he saw Crick’s exasperated expression he said, “but Dr. Crick, we have got it right — we know it’s right,” Crick’s response was, “The point is not whether it’s right. The point is: does it even matter whether its right or wrong?”
BACK TO TEXT