Poisoned by Massage Rather than being DE-toxifying, deep tissue massage may actually cause a slightly toxic situation SHOW SUMMARY

It turns out that massage therapy may be just a bit toxic.This actually shouldn’t come as any kind of surprise, nor is it even much of a problem. But it is interesting, and — more importantly — it is contrary to popular notions. That makes it a perfect topic for PainScience.com.

The idea of “toxins” is often unethically exploited in alternative medicine, usually to sell detoxification treatments.1 So why am I writing about them now? I have argued that toxin talkers should either be specific when they talk about toxins, or stop talking about toxins.

I am going to be specific, and there’s no detox solution for sale here. (And I’m probably sacrificing a small fortune. Pesky ethics!)

Massage is toxic? Probably a little bit, yes — technically. But so is scotch. And hard exercise.

PMSM = feeling a bit gross after massage (or a lot gross)

Flu-like symptoms are surprisingly common after massages. People often suffer from varying degrees of soreness and malaise following firmer massage therapy — post-massage soreness & malaise, or PMSM .23 The worst cases feel like a full-blown flu, except it doesn’t last nearly as long. Severe PMSM is really unpleasant, and its cause is probably unpleasant. Most of this article is about the worst cases, which are much harder to explain than the milder ones, but I devote a section below to exploring the causes of mild cases as well.

Stronger massage tends to cause more PMSM — though the effect is as unpredictable as weather. It is often explained away as a necessary evil, a “healing crisis” that we must endure to get to the benefits on the far side. No-pain-no-gain is the message (mostly unspoken). The effect is often explained more specifically as the symptom of a healthy detoxification process with a (rather doubtful) happy result: unspecified toxins trapped in weary, tight muscles are freed and flushed from muscle, poisoning us mildly as they make their way out of the body via kidneys and livers. There are lot of problems with that mental picture, and they are discussed in detail in Why Drink Water After Massage?

The flushing model is bogus. Massage isn’t “liberating” any toxins that were there when the client walked in the door. If anything, ironically, massage may be creating them — by-products of minor muscle injury. That would mean that massage is actually a “toxifying” treatment, not a de-toxifying one. (This is actually one of the original reasons for the idea that toxins need to be flushed out from the body by drinking some extra water.) If so, it’s interesting how the detox myth has turned itself inside out over the years. Few massage therapists have considered the possibility that the client leaves with a problem they didn’t arrive with. Unfortunately, it’s a strong possibility.

And it’s not such a radical idea. PMSM is real. Something icky is clearly going on after some massages. What?

Rhabdo the Terrible: a medical emergency (which has nothing to do with massage)

Rhabdo kills But it turns your pee the colour of tea first: one of the signature signs. The fact that urine does not look like this a day after a massage is reassuring.

Rhabdomyolysis — or just “ rhabdo ” for short, and for the rest of this article — is a medical emergency that mostly crops up in the aftermath of horrible, crushing traumas.4 Rhabdo can kill, even when injuries are otherwise non-lethal. It is most often seen in the wild in the aftermath of earthquakes and car accidents. It was one of the (wrong) diagnoses suggested by Dr. House in a 2009 episode, “Known Unknowns.”

When muscle is injured, cellular guts are spilled into the blood, most notably myoglobin molecules, which messes with blood chemistry a bit, poisons the kidneys, and turns your pee dark brown. If it gets to the point of kidney damage, it has to be treated with a lot of intravenous fluids to dilute the poisons in the kidneys.

Rhabdo the Terrible, the medical emergency, really has nothing to do with massage. Be aware of this if you mention a connection to a doctor — you will get scoffed at.

But … what if there’s only a little myoglobin? What about mild rhabdo? Can massage cause mild, non-emergency rhabdo? Almost certainly, it turns out.5 In fact, if you get a strong enough massage, it can even — almost — cause severe rhabdo.

An extreme-massage horror story: a case of genuine rhabdomyolysis apparently induced by massage, with kidney danger and everything

Is this fearmongering? I hope not: I share alarming stories consciously and cautiously, only when I think it constitutes legitimate public health education.6

In 2006, an elderly gentleman collapsed with a fever and failing kidneys.7 There are any number of reasons that might happen to an 88-year-old man, but the diagnosis turned out to be a fairly clear cut case of rhabdomyolysis.8 And there was a smoking gun of a cause. A veteran of regular massage for years, he’d had an unusually intense massage the day before. “Intense” is actually a bit of an understatement …

The afternoon before this accident, he received a body massage session for 2 h served by two new massagists [sic] at the same time instead of one. The strength of this massage session was significantly stronger than that of the past.

Safety tip: don’t get a brutal two-hour massage from a pair of “massagists.” 🙄

Clearly this was an exceptional massage. Nevertheless, assuming the rhabdo wasn’t caused by something else,9 his case demonstrates that massage probably can damage muscle. If he hadn’t actually collapsed, he still would have felt perfectly awful — in other words, he would have had wicked PMSM.

And there are probably some other confirmed cases.10 And then there’s the ones I am hearing about directly from my readers…

A reader’s rhabdo story (and the chilling possibility that some people are much more vulnerable than others)

Many people experiencing PMSM are finding this article. They feel rotten after a massage — beaten up and gross, properly sick — and they start Googling. And so, for a couple years now, I have received a steady supply of e-mailed tales of the consequences of intense massages. Many of these are probably not about rhabdo,11 but others are too clear and precise to dismiss.12 It’s impossible to infer real prevalence data about this problem from my deeply skewed sample, and yet there are obviously approximately “quite a few” people out there who are not feeling good after their massages — and pissing the Coke-coloured urine that more or less confirms rhabdomyolysis.

Do you have a story to tell about feeling awful after massage therapy? Please contact me.

Here’s just one good example, which also highlights another important point: that some people are probably more biologically vulnerable to this phenomenon than others. Reader Moriah Dyke of Langely, Canada (shared here with permission):

About a year ago I had a particularly rough massage therapy session and the next day at work I started feeling super sick so I went home (I never get sick, ever) so I layed on the couch whatever went to bed but when I woke up the next morning I literally felt like I had been hit by a bus. I called in sick to work as I could barely get out of bed. The body aches I was experiencing were like nothing I’ve experienced before, I could barely walk! I felt like someone was stabbing tiny knives all through out my major muscles. I stayed in the couch all day and was in so much pain I started googling to see if I could find out what was wrong and I came across rhabdo. My pee was dark brown and I had all of the other symptoms. I was in so much pain I was crying on the couch and so I called the nurses line to see if they could give me any advice. They didn’t believe it was rhabdo but said even if it was all they do is give fluids (and I’m scared of needles) so I didn’t end up going to the hospital but instead took a ton of vitamins and drank an outrageous amount of water and electrolytes to try and help. It took almost two weeks for the body aches to subside 100%. I’ve seriously never experienced anything like this in my entire life. The reason I bring this up is very important. I am in the process of trying to get a diagnosis of Ehlers Danlos Syndrome (a connective tissue disorder) which makes tissue extra fragile. After realizing I might have this condition it seems a lot more likely that massage could rip my tissue to the point where it causes rhabdo which means my experience was probably not in my head at all but a real situation. EDS is severely undiagnosed and some people believe that 1/200 people could have his condition with only 1/5000 being actually receiving a diagnosis. This means that a lot of people could be thinking they’re crazy when doctors tell them rhabdo isn’t possible from a massage when in fact they could have a condition that makes it a lot more likely to have this happen. I thought my personal experience and the link between a connective tissue disorder and rhabdo might be of benefit to you in any future articles you may choose to write. Moriah Dyke, Langley, Canada

Moriah is right: EDS is both underdiagnosed and surprisingly common,13 and it is a real and worrisome possibility that people with EDS are at much greater risk of injury when subjected to powerful massage. It’s probably even worse, in fact.

EDS is part of a spectrum of connective tissue diseases that are all basically about fragility of tissue.14 Most have genetic markers, but not all: hypermobility-type EDS, the most common sub-type of the disease, has not yet been linked to a gene. People with EDS suffer from a wide array of strange musculoskeletal pains and problems,15 many of which drive them to seek therapy, and many massage therapists are all too likely try to treat them by vigorously stretching their connective tissue (fascia) — precisely the opposite of what they need, but it’s an extremely popular trend in therapy, based on misguided enthusiasm for the idea that fascia gets stuck or deformed.16

I shudder to think how many people with pathologically fragile fascia have been subjected to treatment specifically intended to stretch fascia. But even without that specific therapeutic goal, these patients are probably much more easily harmed by any kind of “deep tissue” massage, and they may account for many or most stories about post-massage rhabdomyolysis. It’s conceivable this is a common collision of pathology and manual therapy that almost no one is aware of, patients or practitioners.

Disintegrating muscle tissue!

Rhabdo the Terrible is mostly defined by nasty muscle damage and kidneys dying from myoglobin poisoning — right before you die. It’s the kidney damage that particularly makes rhabdo a medical emergency. But there’s a lot of other things going on — a cocktail of substances that cause a lot of other symptoms (ahem, malaise) many hours before your kidneys are wounded.

Notably, frank trauma is not the only way to get rhabdo, just one of the worst and most obvious. Instructions for releasing lots of myoglobin into the blood:

Step 1: Physically crush muscle.

You’re done! But rhabdo is not just caused by “crushed” muscle but by muscle that, in the words of Wikipedia, “rapidly breaks down” … by any means.

Such as? Space alien disintegrator rays? Giant monster fly regurgitating digestive enzymes onto your quadriceps? How, pray tell, does muscle ever “rapidly break down”?17

This is where things get a bit weirder.

Rhabdo the Merely Unpleasant (a.k.a. recreational rhabdo)

Read up on rhabdo and it becomes clear that while the worst cases are caused by things like buildings falling on people’s legs, there are plenty of other less traumatic causes:

a variety of unusual metabolic states

miscellaneous drugs, toxins, and infections

extended tissue compression (e.g. a long surgery)

both hypo and hyperthermia

and even just extreme exertion

What this odd list of causes tells us is that acute rhabdomyolysis is the tip of a physiological iceberg, the bad end of a broad spectrum.18 Muscles will obviously spill their chemical guts in response to much milder stresses and forces than overt crushing.

Relatively minor, exertional rhabdomyolysis is actually common, and even has a name: “white collar rhabdomyolysis.”19 That term was coined by Knochel in 1990 because rhabdo was striking recreationally extreme athletes — people who voluntarily work themselves into a sorry state.20 You could also call it (for fun) recreational rhabdo. Another well-known source of rhabdo cases is boot camp: “large numbers of [recruits] may have myoglobinemia … .”21

After a bit of browsing through the literature, I have the impression that you could be rhabdo-ized by an especially hard sneeze.

These are real cases of rhabdomyolysis, with quantities of myoglobin in the blood ranging from mildly oogy to alarming, and plenty of mineral and electrolyte derangement — but they are also generally less severe and less likely to cause kidney damage. They are somewhere in the middle of the rhabdo spectrum.

This is also roughly where the older man landed on the spectrum after his brutal 2-man, 2-hour massage. That case is probably the worst case scenario for massage-induced rhabdo … but it’s also a pretty bad worst case scenario. If that’s what a strong two-hour massage can do, what can a strong one-hour massage do? Maybe to someone with a genetic predisposition to rhabdo?22

Disclaimer: this is obviously all hypothetical

It’s a hypothesis that mild rhabdomyolysis may explain PMSM. It’s based on no direct evidence beyond case studies and anecdotes. But there’s an awful lot of smoke!

Anecdotes are not data, but they are a fine justification for research (which probably won’t happen23). And the undeniable existence of exertional rhabdo makes it highly plausible that milder rhabdo can probably also be caused by other biological stresses. It’s not a big leap from there to realizing that painfully strong massage could be one of those stresses.

This is “just” a hypothesis, but it’s a highly plausible one.

Mild rhabdo as a common denominator in feeling cruddy after virtually any physical stress

To understand common experiences, it is often helpful to learn about their extreme and exaggerated forms. What’s going on here? Turn it up! Acute rhabdo is interesting and revealing because it almost certainly represents the extreme form of a tamer and nearly universal human experience: feeling sore and cruddy after physical stress.

The lower half of the rhabdo spectrum is messy and fascinating. It is undoubtedly biochemically diverse, with the exact cocktail depending heavily on many variables like genes, fitness, and the type of stress. Regardless, if relatively normal people like runners and soldiers can get middlin’ rhabdo, then it is virtually guaranteed that less extreme stresses are routinely drivers of less extreme rhabdo. Much of this would fall well below the threshold of what would ever be diagnosed as rhabdomyolysis. Indeed, at the lowest end of the spectrum we simple have other names for it …

“Soreness,” for instance.

Rhabdo the Merely Unpleasant clearly overlaps — mostly or entirely — with the familiar phenomenon of being really sore after strong exercise (usually called DOMS, for delayed onset muscle soreness). And that, in turn, feels almost exactly like PMSM. Quite appropriately, one of the names for DOMS is “muscle fever.”

These experiences are probably just mild versions of something that can get a lot more dire, but usually doesn’t. But the nature of the mild phenomenon is nicely illuminated by the nature of its more serious versions. Although the biochemical details are absurdly complex, the general theme is not — we are poisoned by the by-products of relatively minor tissue stress.

Even a bit of massage. You can almost define massage as “muscle crushing,” and rhabdo is caused by muscle crush injuries and even much milder damage to muscles. Therefore massage probably causes rhabdo, and it is the most likely explanation for PMSM.

So what? The implications are surprisingly unexciting

This is all very interesting, but it may not be very important.

As I mentioned at the start, “Poisoned By Massage” is a sensational title. I chose it to help promote the article, of course — but I wouldn’t have chosen it if I didn’t also believe that “poisoned by massage” actually is scientifically defensible (as well as provocative and interesting). I think the evidence and reasoning is good, and I have some confidence that massage actually does “poison” us, a little.

But so what? So does exercise! And we aren’t quitting that. It is nearly impossible to progress in fitness without “poisoning” yourself with a little DOMS, almost regularly. It is not entirely unreasonable to call it a “healing crisis” — an unpleasant price to pay for some benefits.24

The issue with massage is that the benefits are much less clear. No one really knows exactly what good massage does for people, medically speaking.25 It’s rather murky. We don’t even know if it makes us “fitter” to adapt to the stress of PMSM. Being toughened up by massage might be as dubious as toughening up your feet so you can walk barefoot — that’s all fine and good, but do you need tough feet? Probably not.

Fortunately, we do know that good massage is intrinsically satisfying as a sensory experience, and that is probably a good enough reason to put up with some side effects. However, I am also sure that I don’t want to dial up the PMSM and embrace it either. It can mostly be avoided with gentler treatment, and probably should be.26

Life is stressful. It is a multi-decade process of adapting to stresses. I’m happy to tolerate a little mild rhabdo along the way — but I’m certainly going to try to minimize it.

PMSM: What about people who feel lousy after a gentle massage treatment?

I suspect it’s unusual for people to get PMSM from gentle massage, and when they do it’s probably mild PMSM, just not in the same league as the worst cases. While this article generates a lot of email from people who feel really rotten after a strong massage, I have yet to receive a report of major malaise after light massage. The combo of sensationally bad PMSM with gentle massage is clearly a rarity. While noteworthy, there’s just less to explain here.

Nevertheless, gentler massage can cause some blahs. I often heard about these less dramatic cases during my career as an RMT, and I’ve experienced a few myself. So I am sure that it does occur, and it would be nice to understand. It’s highly implausible that gentle rubbing could cause significant biological harm, so I suspect the causes are diverse, and mostly don’t have much to do with the massage itself. For instance…

Infections. Many cases are probably explained away by a simple coincidence: sometimes you just happen to get sick soon after a massage, just bad timing. Viral and bacterial infections are more common than massage therapy, and they will collide occasionally.

Infections too mild to diagnose are even more common, but those can still increase our vulnerability to physical stresses significantly. This is surely one reason why we’ve all had days when a familiar workout feels surprisingly hard and makes us more sore than it “should.” Even a light massage in such biological conditions might have the same effect.

Chronic mild pathological vulnerability. In addition to mild infections, there are a variety of diseases and chronic illnesses that can go undiagnosed for years, or even forever, and those might also dial up vulnerability, either transiently during flare-ups, or all the time.

“Sickness behaviour.” The phenomenon of PMSM is so similar to the aching malaise that comes with viral infections that we have to consider both the possibility of actual infections… and the possibility that something about massage has the same effect as an infection, which isn’t as weird as it might sound at first. Feeling gross is technically known as “sickness behaviour,” a set of symptoms generated by an ancient biological system shared by all animals: when threatened, neuroinflammation enforces rest and retreat by making us feel fatigued and fragile.27

I do not know why mild massage would provoke a neuroinflammatory response, but neuroinflammation and sickness behaviour have such deep roots in biology that it wouldn’t surprise me if they can be provoked in surprising ways. Fun stuff to brainstorm about!

Extreme de-conditioning. Consider all the people who are so out of shape that they would feel slammed by a 10-minute jog, a dose of exercise that any fit person would blast through with no ill effect. For the truly unfit, a “gentle” massage might not be so gentle. We shouldn’t underestimate the potency of significant deconditioning. Anyone who has trained really out-of-shape people knows how startlingly fragile they can be.

Emotional and psychological factors. Finally, there’s undoubtedly some psychological PMSM. Even a happy, relaxing massage experience may expose or highlight an exhaustion that was already there, like taking off a mask. Life is hard and many people are running on empty, pushing through the days powered by caffeine, worry, grit, and necessity. Massage is a rare chance to relax and unwind, but it may also have the potential to disarm us, to rob us of our normal defenses against the suffocating fatigue lurking just under the surface. I believe I have experienced precisely this flavour of PMSM on many occasions … and most Sundays, frankly.28

It’s extremely unlikely that PMSM is caused by a Jarisch-Herxheimer reaction

Many massage therapists have speculated that PMSM is caused by a Jarisch-Herxheimer reaction, which is being poisoned by the corpses of dead bacteria during antibiotic treatment. The most polite response to this idea I’m capable of is that it is wildly speculative, citation needed, and good luck with that. It rests heavily on huge optimistic assumptions about the powers of massage, specifically its ability to cause such an extraordinary surge in immune system activity that it could kill off enough bacteria to cause this effect.29

And what infection is this, anyway? Are we also hypothesizing that people with serious enough infections to cause a J-H reaction are also asymptomatic enough that they are seeking out massage therapy?

I’ve been writing about this stuff long enough to avoid categorically declaring that anything is “impossible” — I always want to leave a little wiggle room — but this is about as far out in left field as massage claims can get. For some alternative medicine practitioners, I think “Jarisch-Herxheimer reaction” has just become a handy way to say “healing crisis” in a science-y way.

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About Paul Ingraham I am a science writer in Vancouver, Canada. I was a Registered Massage Therapist for a decade and the assistant editor of ScienceBasedMedicine.org for several years. I’ve had many injuries as a runner and ultimate player, and I’ve been a chronic pain patient myself since 2015. Full bio. See you on Facebook or Twitter.

Afterword: The flushing theory goes down the drain

This entire article started out as an attempt to clarify a point about “flushing” in my article Water Fever and the Fear of Chronic Dehydration. The effort got a little out of hand, and I ended up with a 3700-word article about rhabdomyolysis. However, I still need to address the flushing thing …

Photograph of a glass of water.

If PMSM is basically a light poisoning, does this validate the popular practice of advising massage clients to drink extra water? Mostly no — it’s not specifically, medically relevant.30 It’s sensible to avoid compounding mild rhabdo with dehydration. But it’s sensible to avoid dehydration, period.

If acute rhabdo is treated with IV fluids, doesn’t that suggest that drinking water would help? In mild rhabdo, we’re not worried about kidney damage at all.31 And drinking an extra glass or two of water wouldn’t (remotely) do the job anyway. Indeed, there’s an ironic catch-22: if you drank enough water to successfully dilute a dangerous concentration of myoglobin in your kidneys, you’d actually poison yourself. With water.32

Consider: Can you “treat” the much more familiar problem of DOMS by drinking extra water? Answer: definitely not. Try drinking three extra, big glasses of water the next time you’re super sore after a big workout. Still really sore? You can count on it.

In principle, the only medical condition that can be effectively treated by drinking more water is … dehydration. A number of disease processes and even toxins are dehydrating, which can in turn be treated with hydration. The obvious example is alcohol.33 But neither massage nor rhabdomyolsis is “dehydrating.” (I’ve actually heard the claim that massage is hydrating — but that’s too kooky to bother debunking.)

Dehydration is inherently dangerous, and will particularly aggravate any condition where the concentration of toxins in your body fluids is a factor, and this can be helped by diluting the toxin with a higher blood volume — but only a little, and not enough to dilute toxins.34 Acute rhabdomyolysis is treated with intravenous fluids because, again, you literally cannot drink enough to dilute the toxins enough to protect the kidney.35

Many people will guess that drinking makes you pee more, which means more kidney action, which means more processing and filtration of some blood borne toxins — but the logic is just the same as with blood volume. It’s true-yet-trivial.36

Dehydration is worth avoiding in itself, of course, and it’s not illogical to make sure you avoid it after a massage: who wants both pre-rhabdo and dehydration at the same time? Not me. Unfortunately, in no way is extra hydration really “protective” — there’s just not that much difference between hydrated and un-hydrated.

APPENDIX: Responses to criticisms

I certainly expected to be criticized for being “negative” about massage in this article — and I was criticized for it — but I was also called out for overconfidently presenting a theory without evidence. That’s ironic: I’ve put in plenty of time fighting hype about premature conclusions, and I would hate to be the source of one. Am I?

Whilst not disputing that your hypothesis may very well be correct and it is an interesting and plausible position, I feel that your conclusions are just a little strong without being backed by sufficient evidence. “Inner West Mobile Massage” commenting on Facebook

I appreciated the spirit of that criticism, and I even agreed with it and immediately changed one key overconfident sentence in the conclusion. But as I reviewed this whole article looking for other signs of overconfidence, my concern eased. There are a lot of qualifiers and equivocation here! I say “maybe” a lot. It’s clear from the style that I’m hypothesizing, thinking out loud. I do like the theory, and I suspect it’s probably correct, but I don’t think I present it as a sure thing — nowhere close.

More criticisms arrived. On Twitter, for instance, @SwoleClient accused me of “unfounded claims,” arguing that I was basing my entire argument on a single case study. Others echoed the sentiment.

I do not agree with that. There are two main issues here:

confusion about what a “claim” is, and where the burden of proof is levels of confidence and evidence

“Claim” need not apply here

A claim is any unverified assertion. But not all claims are created equal. In health care and health science, “claim” implies a more self-serving assertion. If a claim could be used as a bullet-point in a sales pitch, it’s more claim-y. If it makes you (or your profession) look better, it’s more claim-y. And the more claim-y it is, the more it needs to be backed up.

This special case of the word claim comes from the thorny ethical challenges with selling care to sick, hurt people. All claims need critical appraisal and verification, but it’s just not as ethically critical if it has no claim-stink. Sagan’s idea that “extraordinary claims require extraordinary evidence” is not just about alien abductions and lake monsters. It’s also, in spirit, about more mundane but self-serving and profitable claims — a more common ethical hazard than truly extraordinary claims.

I presented my theory to cast doubt on classic self-serving claims, claims that serve the interests of massage therapists: the popular and specific claim that massage “detoxifies,” and the more general claim that massage is beneficial (or at least safe). The “claim” that I made in Poisoned by Massage is more self-defeating than self-serving. It superficially contradicts my widely published opinion that people should purchase massage services and devote considerable energy to self-massage (although I explain in the article that it’s not really much of a concern). My “negativity” about massage and many other treatments does great harm to my bottom line. I could probably make much more money just by shutting up about things like this.

So the accusation of “unfounded claim” doesn’t fit well — technically correct, but definitely wrong in spirit. What I presented is just a partially supported theory.

There is exactly no evidence whatsoever that massage detoxifies. But I presented some evidence and a plausible theory that it does, in fact, do just the opposite. This is more about putting a dent in the detoxification claim than proving my own hypothesis — my own case simply has to be “reasonable” to cast significant doubt on the claim.

Levels of confidence and evidence

Many professionals believe (or fear) that evidence-based medicine is uptight and narrow, and ignores their clinical experience (even though EBM has always emphasized that evidence is only one important factor in clinical reasoning, see Science versus Experience in Musculoskeletal Medicine.).

Now, when I defend a theory with imperfect data, I got flak from some of the same people for not presenting enough evidence! Bah.

My case for rhabdo as the cause of post-massage soreness and malaise was not just based on a single case study, as several critics implied. I argued it from a few different angles, and supplied a fair bit of “circumstantial” evidence (indirect evidence). Chalk the whole thing up to “you based everything on one case study,” as a few people did, is a facile synopsis.

But neither did I say that the evidence was strong or that my conclusion is airtight. The level of evidence was modest, the reasoning reasonable — and my level of confidence matched it.

It’s a trap! An example

One crafty critic tried to trap me in an apparent inconsistency:

Earlier this year you complained that there wasn’t enough evidence for the claim that massage reduces inflammation. But now you’re claiming with weak evidence that massage causes rhabdo. What gives?

Here’s what gives: the researchers involved in that study made a big massage-boosting claim that was implausible to begin with in any number of ways, and which was poorly supported only by only a single indirect line of evidence. The claim was big, so the burden of proof was heavy, and yet all they had was some extraordinarily elaborate test tube evidence, full of problems, and far removed from any sound clinical implications. And yet they summed it up very confidently for the media and the journal very definitively as “massage reduces inflammation.”

Simply not the same thing.

A missed opportunity

Histrocially, there was something wrong with this article, but no one caught it: its most significant outstanding flaw for a long time was the absence of any discussion of alternative explanations for the phenomenon of post-massage soreness and malaise. “How else can I explain this?” is a pretty basic part of critical thinking, and it’s missing. I didn’t go there until mid-2020, when I added the section about milder cases. And there’s still more I could do. Maybe next month.

Related Reading

The major myths about massage therapy are:

The complete list of dubious ideas in massage therapy is much larger. See my general massage science article. Or you can listen to me talk about it for an hour (interview).

And massage is still awesome! It’s important to understand the myths, but there’s more to massage. Are you an ethical, progressive, science-loving massage therapist? Is all this debunking causing a crisis of faith in your profession? This one’s for you: Reassurance for Massage Therapists: How ethical, progressive, science-respecting massage therapists can thrive in a profession badly polluted with nonsense.

Notes