EXCERPT This article is an excerpt from PainScience.com’s ridiculously detailed tutorial about trigger points (muscle knots), which contains more detail and many other tips and tricks for tough cases of muscle pain.
In the weighty text Muscle Pain, expert authors and researchers Dr. David Simons and Dr. Siegfried Mense are pretty enthusiastic about stretching as a treatment for trigger points, also known as “muscle knots” (sore patches in soft tissue). Stretching is mostly quite disappointing as a therapy for other problems — see Quite a Stretch. If stretching actually helps muscle pain, it could be one of the only good reasons to stretch other than pleasure.
Unfortunately, it’s a pretty a big “if.” Trigger points are controversial idea, and it’s not clear that stretching will help even if trigger points work the way Simons and Mense believe they do.
They propose that “essentially any technique that elongates the muscle out to its full stretch length” constitutes effective treatment for trigger points therein. “A newly activated, single-muscle myofascial trigger point is usually remarkably responsive to simple stretch therapy,” they write. Stretching “by almost any means is beneficial … At least five ways can be used to augment simple muscle stretch.”
They make stretching for trigger points sound pretty good!
Probably too good to be all true. A few pages later, they also write that it has (understatement!) “not been firmly established” that stretching trigger points is helpful, emphasizing that they are making educated guesses. No kidding.
Assuming that trigger points exist as described by Simons and Mense, and if stretching ever actually works, it probably works about the same way that stretching out a calf cramp works: you win the tug-of-war with spasming muscle. It just happens on a smaller scale. This is superficially plausible. Certainly stretching is the only defense against big cramps.
Here’s a quick review of their theory about what a trigger point is: a sick, poisoned patch of spasming muscle experiencing a metabolic bad day, a situation known as an “energy crisis.” It is consuming lots of fuel and excreting lots of junk molecules at exactly the same time that it is choking off its own blood supply. Waste accumulates and irritates nerve endings (causes nociception), and everything goes downhill. The main idea is that it’s a vicious cycle.
If the muscle fibres in a trigger point could be fully elongated by stretching the muscle, they cannot burn fuel. Muscle fibres can burn fuel only when the working molecules inside the muscle fibre are mostly overlapping. When stretched out and disengaged, they cannot work, like a hamster without a wheel to run in. According to Simons and Mense, the stretch-state disengages muscle fibres, interrupts contraction, and presumably allows the energy crisis to abate, the vicious cycle derailed a little more with each passing moment of stretch.
This is state-of-the-art of trigger point science, such as it is. It is one of the most educated guesses available, from credible authors on the topic. This is about as close as we’re going to get to a really good therapeutic reason for how stretching might help trigger points.
Alas, there are major concerns.
Even if all of the above is correct — which is granting quite a bit — there would still be many circumstances in which you could not realistically hope to win a tug-of-war with your trigger points. In fact, if it works at all, it probably mostly only works on the milder cases that don’t matter very much in the first place. This is not an attractive equation: a treatment that probably only works on the mildest cases, if it works at all, which it may not, because it’s all based on a controversial theory.
Simons and Mense write that stretching works primarily for “newly activated, single-muscle” trigger points, presumably because they think that you can more easily win a tug-of-war with a milder contraction knot than a meaner one. Fair enough. Newer trigger points are probably milder, on average, and milder trigger points probably aren’t contracting as powerfully. The less extreme physiological circumstances (less painful!) mean that a defensive contraction is relatively unlikely, and that the trigger point is not so tough that it can’t be pulled apart. That is, it will “fight back” less (if at all).
But what about meaner trigger points in shorter muscles? Exactly how you are supposed to pull apart a powerful contraction knot — muscle fibres in full spasm — with anything less than a pliers and a vice and a glass of bourbon? We almost certainly do not have the leverage or pain tolerance required to actually elongate the contraction knots that matter. And logically, if Simons and Mense are correct about how this works, a little pull is not going to do the job — you have to elongate them enough to substantially disengage the overlapping proteins that are burning fuel. On the same page I’ve already quoted extensively, Simons and Mense emphasize that a trigger point must be “fully” elongated in order — theoretically — to have any effect on a severe energy crisis.
In many muscles, this is biomechanically implausible, probably impossible. In The Unstretchables, I describe “eleven major muscles you can’t stretch, no matter how hard you try,” simply because anatomy makes it impossible to pull on them much. And even when you can strongly stretch a muscle, you may take up all of its slack without affecting the trigger points inside of it at all. …like trying to extend a powerful short spring by pulling on it with a meter of bungie cord. In fact, it’s extremely unlikely that you can elongate a strong contraction knot when it’s in a long muscle — you have no good “grip” on it. It would be like trying to extend a powerful short spring by pulling on it with a meter of bungie cord. Good luck!
And then there’s the pain. After emphasizing that you must “fully elongate” trigger points to treat them, Simons and Mense also wisely caution that the stretch must be applied “slowly and only to the onset of discomfort.” I agree.
Unfortunately, there is no hope of “fully elongating” any seriously hurting muscle by applying stretch “only to the onset of discomfort.” By their own theory, discomfort will start when you’ve only begun to tug on a contracted trigger point! If you stop there, you’ve done nothing — either in theory or in practice. Such a gentle stretch could probably only be useful in the case of the most minor trigger points. Stretching for such minor symptoms might feel good to someone, but it has no therapeutic importance to anyone troubleshooting serious pain!
People often have such acute muscle pain that they can’t bend over to tie up their shoes. They can’t fully elongate a Slinky without an onset of discomfort, let alone their trigger-point-riddled muscles. It is these persistent and serious ambiguities that keep me from getting too excited about the potential of stretch to resolve trigger point pain … despite the fact that it sounds good on paper.
The grumpy elephant in the corner here is that the energy crisis theory could be wrong, in which case good luck “interrupting” it with stretch.
What if trigger points are “all pain,” a mainly sensory phenomenon and not a physical one? What if they are a symptom of a neurological cause of pain, and have nothing to do with muscle physiology at all? This is (basically) what other experts believe.
Stretching might still help even “pure pain” in muscle — even if there isn’t a contraction knot. In fact, ironically, it’s actually more plausible than what Simons and Mense proposed (though it still has problems).
We know (pretty well) that a diligent stretching habit increases flexibility, but not by actually changing muscle and connective tissue. Fascinatingly, it is probably just our tolerance for stretch that increases with practice (see Weppler et al). Muscle elongation is normally strictly limited by the brain and spinal cord, and only with repeated exposure to strong stretch can we “get used to” the discomfort and gradually push the limit back.
Trigger points might be a symptom or side effect of the nervous system imposing excessive limits on muscle extensibility. If so, they might — sometimes, when the planets align — fade away as we train ourselves with stretching to tolerate greater muscle extensibility.
Not a bad theory, eh? That’s my idea. It has some attractive qualities. But I am mainly just emphasizing the complexity of the problem and the many reasons why it’s not clear that stretching can actually help trigger points — but might be able to.
In the full version of the trigger points tutorial, you’ll learn about the surprisingly practical problems with using stretching as a therapy, how muscles with trigger points may already be overstretched, and why the anecdotal evidence — even though it’s strong — just isn’t good enough to get excited about it, as well as additional details left out of the sections above.
And stretching is the tip of the iceberg — there’s much more to know about self-treatment of trigger points. I’ve written a lot about stretching because it’s an interesting subject, and because a lot of people place a lot of their hopes on stretching. But there are probably (much) better ways to treat muscle pain. The tutorial explores them all. It’s book-length and required reading if you’re serious about tackling trigger point pain. Buy it now ($19.95) or read the first few sections for free.
I am a science writer, former massage therapist, and I was the assistant editor at ScienceBasedMedicine.org for several years. I have had my share of injuries and pain challenges as a runner and ultimate player. My wife and I live in downtown Vancouver, Canada. See my full bio and qualifications, or my blog, Writerly. You might run into me on Facebook or Twitter.