In biology, nitro is quickly converted to nitric oxide (NO; not to be confused with nitrous oxide, which is N₂O). The NO is actually the active ingredient, and a powerful vasolidator … maybe anti-inflammatory … maybe analgesic … and, most importantly, maybe a tendon builder. So maybe it’s good tendinitis medicine?

We’ve needed some superior science on this for ages, and we finally just got some from Kirwan et al, a nicely controlled test of nitroglycerin ointment done the way most of us would do it: smear some on daily for a while. What have we learned from their science-ing?

Kirwan et al. tested topical nitro on a few dozen Irish folks at a Dublin hospital. They compared nitro to an “aqueous cream, which contained no ingredients that would aid in tendon recovery.” (And yet you can easily find examples of cranks making the oversimplified claim that tendons need to be hydrated. 🙄)

Everyone also did the same exercise program for six months: the Alfredson protocol (predictably), a bunch of calf exercise made fiddly by doing them the eccentric way (loaded elongation). “It is known” that the Alfredson protocol is no better than simpler weighlifting. The authors reference that evidence from 2015, explaining that it was “published after this trial was designed.” (So this trial took at least a decade to pull off? Wowsers!)

All that exercise, plus time, means that everyone was likely to get better, and they did. But did nitro-smeared heels heal faster?

The answer was … no difference. An utterly negative result on its face. Nitro conveyed no advantage whatsoever.

It did convey some headaches though, which is a well-known side effect. (It’s also a potent migraine trigger in people with that vulnerability.)

[Image caption: This is the GTN ointment that was used in the study. Availability of nitro ointments and patches is patchy around the world. For instance, “it was not possible to use altered or cut transdermal GTN patches for the purpose of this trial, in line with European Union regulations.” Most nitro ointments are for anal fissues, and have re-for-rectal names like Rectogesic, Repane, and (on-the-nose) Recto-Relief. (Get a load of the cheesy anal-pain graphics here! It also includes a fully illustrated guide to usage, and I do mean FULLY.) You can use the made-for-butts nitro products on your tendons. It is exactly the same stuff.]

This is why one study is never enough

This new result is the opposite of another quite old result, from a similar 2004 trial, also fairly rigorous. To be clear:

• In 2004, Paoloni conducted a good quality trial with a strongly positive result. 👍🏻
• In 2024, Kirwan conducted a good quality trial with a strongly negative result. 👎🏻

What gives? Kirwan et al. speculate that it could be chalked up to either their different outcome measures and/or dosage. Paoloni et al. used more nitro, from a patch, and reported both more benefit and more harm: more tendinitis relief, more headache grief! This could be tidy example of how a relatively small detail might make all the difference, and explain how two good quality trials can produce completely different results.

Figure 3, Kirwan et al. 2024, British Journal of Sports Medicine

[Image caption: That is about as simple and clear as a graph of trial results can get! Even where the GTN and the placebo differ, the gap is much smaller than the error bars. Just absolutely no difference. But — and this is THE question about this study — would a higher dose of GTN have pushed that blue line higher than the pink? That’s not just speculation: that’s what Paoloni et al. reported in 2004.]

The conclusion of the new study is less pessimistic than its results. On the one hand, “our results do not support the use of topical GTN ointment in treating Achilles tendinopathy.” No, indeed, they do not. And despite using ointment instead of patches, they had reasons to think it was enough. Ointment “has been shown to be as effective as patches,” based on a study of anal fissures. But butts probably don’t heal the same as heels, so that’s hardly conclusive.

And so, on the other hand, maybe this new trial was negative just because ointment did not deliver enough nitro:

In light of our incomplete understanding of tendon pathophysiology, the study of GTN is warranted, as basic science, animal and human studies have confirmed NO as an important chemical messenger in tendon pathology and repair.

If the only two good trials were both negative, I would say “case probably closed.” But as it is, I think it would be a mistake for a careless skeptic to point to this paper and scoff at nitro for tendons. I think this is an unusually legitimate example of “more study needed.”

See my guide to Achilles tendinitis for some more information (and colour) about topical glyceryl trinitrate.

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Shockwave therapy is also more painful than ultrasound or massage guns because … it actually does damage. Not a lot, of course. It’s “microtrauma”: minor, diffuse damage, which is sometimes obvious due to minor bruising, but mostly only visible in a microscope.

But what’s the point? Why slap tissues with much higher energy than ultrasound? Why break anything?

Today’s post is all about shockwave therapy’s Big Idea, the why of the thing, the main reason that it’s supposedly effective, how you can supposedly gain from that pain. And that reason is (drum roll please) …

Damage … is … healing! 🤯

Which sounds a bit ridiculous. Would you be more impressed if I said that the core hypothesis of shockwave therapy is that microtrauma hormetically stimulates cellular regenerative processes? Oooh, that’s more like it! Talk nerdy to me, baby!

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“Nobody chooses chronic illness… So, before judging, remember that they may have done everything right, but illness is unpredictable, unfair and unforgiving. The fact you see [them] out at all is a testament to their efforts to live, despite the pain.”

Sarah couldn’t exercise without feeling awful, due to an invisible pathology that evaded diagnosis for a while: adrenal insufficiency and growth hormone deficiency, caused by [empty sella syndrome](empty sella syndrome)).

“It sounded bizarre to me when my doctor at Mayo Clinic told me that exercise intolerance was a real thing, but it also made me feel better to know that there was a legitimate reason I felt so bad after walking only half a block.”

Not everyone can exercise, because pathology! If you have cancer, no one hassles you for taking it easy. It’s hard to exercise when you’re sick. Duh.

But when the sickness itself is contested? The inability to exercise is contested too! If you have ME/CFS or fibromyalgia, or something else that just hasn’t been diagnosed yet, you will be accused — or insidiously suspected — of being lazy, of being the author of your own malaise.

We use the weird term “exercise intolerance” to describe people who can’t exercise because they’re sick … which should be obvious, but it isn’t, because the illness isn’t obvious. And there is plenty of non-obvious illness out there.

I shared this on Facebook, where it attracted quite a few good comments. (Also a lot of miracle-cure spam! But I delete those fast.)

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I used that service for eighteen years! And more reluctantly every year.

In theory, that infinite avalanche of data can inspire savvy strategic publishing changes. Maybe the articles with the ten worst “bounce rates” on the site should have more infectious intros? Write some sparkling prose and then sit back and watch those bounce rates improve? Maybe. It’s a seductive idea for anyone with a spreadsheet-loving mind.

In practice? Pffft. 🙄 I tried hundreds of data-driven content tweaks like that back in the day and frankly I never got one clear dang win. It was always like trying to knock over a punching dummy. I was often amazed how even glaring glitches would have no effect.

For example, online businesses work hard to optimize their buy buttons and cart funnels. And you’d really think that a big formatting mistake — something truly fugly — would really slam “clickthrough rate,” right? Surely? Frank errors “should” produce more dramatic signs than minor design changes!

But nope. Again and again I saw bricks tossed into the data pond without making so much as a ripple. Weird. 🤷🏻‍♂️

It’s almost like people don’t much care what a buy button looks like. Like they probably accept or even embrace the quirks of a small business.

See enough examples like that and you start thinking maybe finicky A/B testing of tiny 🤏🏻 design differences might be a waste of your frickin’ time!

And so good riddance. I have better things to do, and I always did. I shudder to think how much time I sunk into those experiments. Now I just write/publish what works for me … and to hell with analytics and SEO.

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Unfortunately, when I tried the stuff, I quickly discovered an infamous side effect I hadn’t heard of: my chronically poor sleep got even worse! Which is bad for pain and injury rehab. So I can now add to the anecdotal evidence that creatine can make sleep as thin and unsatisfying as skim milk. (Obviously it doesn’t affect everyone this way. Biology is messy, people are different.)

[Image caption: Creatine monohydrate is notorious for causing shallow sleep.]

But here’s an unexpected twist in the creatine plot …

Some people claim creatine improves mental alertness despite the fact that it messes with sleep. Could creatine take the benefits of sleep from us at night, and then give them back during the day? Such a thing could be true, but it is a significant claim. Just helping with the effects of sleep deprivation would be a big deal in itself, but mitigating it as well as causing it? A drug that treats its own side effects?!

I have doubts. The evidence bar has to be set high for us to swallow that hypothesis with our creatine … and I don’t think the science we have comes anywhere close to clearing it.

ResilientNutrition.com takes a stab at this. Their 2021 article cites Kreider et al. — a general review of creatine that barely mentions this topic. 🙄 Just one sentence, with one relevant citation to McMorris, a very small 2007 study of just one facet of this complex question … with a mostly negative result. So this is a classic example of a bogus citation. “I do not think that citation means what you think it means.”

To be fair, RN’s article does go on to cite a couple more studies — but both small ones from the same small research group. Their data is worth considering, but it’s not much to go on.

The claim is an educated guess at best. Meanwhile, we do know for sure that sleep deprivation is serious stuff. How many systems are impacted by it? Probably all of them! Even if creatine absorbs some of that impact, what are the odds that it can protect us from all of it?

It’s probably unwise to take a supplement with a known harm because it might compensate for it partially.

But! I would be willing to consider taking it if I’ve already slept badly for other reasons. Some 2024 evidence does support that strategy: “a high single dose of creatine can partially reverse metabolic alterations and fatigue-related cognitive deterioration” (Gordji-Nejad).

Have you experienced creatine-wrecked nights? Have you felt fine or better during the day despite that? Let’s hear your anecdotes! I think they’re all we’re going to have for a long time.

This post is an excerpted update to my insomnia guide.

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“While there are lymph nodes in both armpits, there is no expulsion of lymph from the left armpit, an observation that should be apparent to anyone with armpits.”

Indeed! I have armpits, and that is apparent to me. (That is, it is clear that neither my left nor right armpit is a lymph-leaker.)

Skeptical pharmacist Scott Gavura ended up having to write that sentence while debunking some particularly weird health claims about magnesium for ScienceBasedMedicine.org, such as: “3/4 of the waste in your lymph expels through your left armpit” and “rubbing magnesium oil on your feet will eliminate body odour.”

What the hell? It never cease to amaze me how confidently people can just make shit up and pretend it’s actually knowledge and wisdom. Homo sapiens is just astonishingly good at bullshit! Wikipedia on bullshit:

“The term ‘bullshit’ is sometimes used to specifically refer to statements produced without particular concern for truth, clarity, or meaning, distinguishing ‘bullshit’ from a deliberate, manipulative lie intended to subvert the truth.”

Scott’s whole article is worthwhile, and I’ve added this snippet to my Epsom salts guide, which explores magnesium-as-medicine in detail.

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This post? Very general! This is about the big shockwave picture. What the heck are shockwaves anyway? Are they different from ultrasound? How? What's the point? Do they work? Et cetera.

98% of information about this popular high-tech therapy is published by manufacturers or providers. It is just a 🤏🏻 wee bit biased. But the salamander, of course, is refreshingly free of those vested interests.

[Image caption: Super-duper ultrasound]

[Image caption: ESWT is high tech. The main differences for the patient? It ain’t cheap, and it’s much more intense.]

The pressure wave therapies are huge in physical therapy: both ultrasound therapy (US) and extracorporeal shockwave therapy (ESWT). Both are used to treat pain and injuries like plantar fasciitis, stress fractures, muscle strains, or runner’s knee.

Therapeutic ultrasound has been one of the staples of physical therapy since the 1950s. It is still widely used in physical therapy clinics today, and you can buy your own DIY ultrasound machine at the drugstore. It’s fancier and more potent cousin, shockwave therapy, has been steadily replacing it in the 21^st Century.

Shockwave therapy is ultrasound… reborn!

Although ultrasound and shockwave therapy are different … are they really? All their variants are used in much the same ways for mostly the same conditions. They are both vibration delivery systems, intended to stimulate or even damage tissue — which might, depending on the details, induce regenerative and anti-inflammatory effects in injured bone, cartilage, and tendon. They both belong to a family of vibration therapies with massage guns, jacuzzis, and vibrating exercise platforms, which are all very similar in spirit.

Fast sound waves versus slow shock waves

Shockwave therapy is often considered a new kind of ultrasound, but shockwave therapy isn’t “ultra” sound — it’s infra!

Also not actually “sound.”

Ultrasound uses high-frequency sound waves, above the range of human hearing (> 20,000 Hz) — which vibrates tissue so quickly that it warms up from the friction, like a gentle microwave. The point of ordinary therapeutic ultrasound is that it’s like a heating pad with a more penetrating warmth. It’s mostly a “heat ray.”

It’s cheap, ubiquitous, harmless … and mostly useless.

Shockwave therapy: like ultrasound, but … more

Shockwave therapy is, weirdly, much more like a powerful vibrating massage “gun.” It looks almost exactly like ultrasound: a gadget that you pass over an injury like a magic wand. But it’s the more-is-better cousin of therapeutic ultrasound — more intense, more technologically impressive, more expensive. The price has come down a lot in the last decade, but even now it will run you at least $100 per visit, often much more, with a typical prescription of three to six treatments.

Shockwave therapy generates pressure waves that slap tissues with much higher energy, travelling faster than the speed of sound (in flesh), about 1500 meters per second.

But those waves are also extremely infrequent, compared to ultrasound. They come at a leisurely tempo that you could almost dance to — mostly under 10 Hz, thousands of times lower than ultrasound. In fact, a typical five shockwaves per second (5 Hz) is quite a bit slower than tap dancing, which can get up to about 18 Hz! But it is way below the range of human hearing, which starts around 20 Hz. So shockwave therapy is closer to infrasound than ultrasound.

Shockwaves also aren’t technically “sound” waves: they are high-energy pulses of pressure rather than continuous oscillations — like sharp mountains rather than rolling hills.

[Image caption: A schematic contrasting the overall shape of shock waves, sound waves, and ultrasound waves … not to scale! Ultrasound waves are dramatically more frequent that shock waves, or even low-frequency sound waves: you might only get a few big shock waves per second, but ultrasound machines will pump out more than 20-30 thousand much smaller sound waves in the same second! Any properly scaled diagram that shows one of them clearly will render the other effectively invisible.]

What’s the “extracorporeal” about?

“Extracorporeal” just means “generated outside the body,” which seems obvious — you don’t swallow it, and it’s not a surgical implant. Shockwave tech was adapted from a revolutionary method of smashing gall stones and kidney stones with pressure waves, one of the greater victories of modern medicine, back in the 1980s. It was called “extracorporeal” to emphasize a feature that we take for granted today, but was truly amazing at the time: you could deal with the stones without having to cut into someone, or insert a probe up the urethra (which, eek, had been a common technique).

In a physical therapy context, we don’t much care that there’s no scalpel work or urethral violation … so the “extracorporeal” is often dropped. (And sometimes not dropped, because big words make things sound important!)

What’s the point?

It’s not clear why kidney-stone smashing tech was adopted by physical therapy. Why “slap tissues with much higher energy than ultrasound”? What’s the point? The goals of ultrasound and shockwave therapy mostly overlap: to “stimulate” tissue, which is the same vague rationale for nearly all gadget-powered treatments. But there are at least two significant differences:

• Shockwaves are too slow for thermal effects, but ultrasound is literally warming, and can even cause burns — but this is never done deliberately.
• But shockwaves can cause physical trauma, which ultrasound cannot do — and this is done deliberately. (They can also break up calcifications, which is the technology’s original claim to fame: it can smash kidney stones. But this ability is of much less certain value in musculoskeletal medicine.)

It is certainly a different kind of stimulation. But the evidence for its usefulness is a classic example of “promising” evidence that falls apart when you dig into it. Shockwaves have some excellent medical uses, but … vibrating tendinitis? It’s not so clear. Downright speculative, actually!

Like basically every gadget and technique in manual therapy, shockwave therapy is not based on evidence. I review some of that evidence in my full guide to ultrasound and shockwave therapy, but the summary is really simple, and it follows a classic pattern in this business: the strongest evidence is negative, and the positive evidence is the weakest.

I’ve been working on this a bunch lately, levelling up my shockwave knowledge, and this is an adapted excerpt of some of the new material. I’ll share another excerpt soon, to wrap up this short series of posts about shockwave therapy, about it’s sketchiest claim: that shockwaves helps by … harming?

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A scientific review says it works though. So … checkmate, irony!

Today’s featured study is Yazdani et al., a new Iranian review of trials of treating Dupuytren’s contracture with shockwave therapy. Treating what with what? Before we review this review, let’s review what it’s reviewing — which is probably the most interesting part. “Dupu” is weird, and so is shockwave therapy.

[Image caption: Dupuytren’s contracture, showing significant progression of tendon fibrosis, pulling the finger into permanent flexion.]

Dupuytren’s and shockwave therapy in a nutshell

Dupuytren’s contracture is an odd disease of slow thickening and lumpiness of the fascia and tendons of the palm, sometimes painfully. The disease is mostly genetic, but can also be triggered by working with vibrating tools for many years.

Which makes shockwave therapy an odd choice of treatment, because — dramatic pause! — shockwave therapy is basically vibration therapy. Yes, you heard that right: vibrations for a condition known to be triggered by vibration! Welcome to my weird world.

Of course, there are many kinds of vibration. Music is all just vibrations, but ranges from inspiring genius to ear-stabbing torture. I’m fine with the way my electric toothbrush vibrates, but the ultrasonic scaler at the dentist is Satan’s work. And clearly a few brief doses of shockwave therapy is not really the same as years of pushing a lawn mower. But I still say it’s odd, ironic, and not entirely risk-free to blast a vibration-triggered disease with more vibrations.

Shockwave therapy is a sibling of ultrasound, but uses pressure waves: low frequency but fast, high energy waves that smack into tissue much harder than sound waves. This makes it even more closely related to massage guns, and with the same vague goal of stimulating tissue. No one really knows exactly why shockwave therapy would work, although there’s no shortage of speculation.

So it’s just a potent vibration, applied to Dupuytren’s because it has a reputation for being good for many orthopedic conditions for unclear reasons — a reputation that is not even deserved! There’s mostly just an absence of shockwave evidence, and what evidence we do have is — as usual — cherry-picked and overrated by the many professionals who sell shockwave therapy, and sincerely don’t want to read the fine print. (Read more.)

So, do shocking waves help people with Dupuytren’s? Some thin science says “yes!”

Yazdani et al. auditioned twenty-six studies, tossed out twenty, and reviewed the remaining six teeny tiny trials — just 145 patients covered by all of those. But studies don’t have to be big to be worthwhile, and these researchers judged five to be “good” quality, and one “fair.”

I think they might have been a bit too generous.

But — good news, everyone! — those six studies of uncertain quality collectively showed “remarkable improvement” in pain and function, as measured by the pain-scale and various disability questionnaires. One study also reported improved grip.

And another reported actual shrinkage of the distinctive bumps and lumps of Dupuytren’s contracture! So maybe shockwave therapy can “melt” contractures somehow? That would be a way bigger deal than merely improving pain and function — that’s changing the course of the disease. If it really does, that’s some crazy physiology, fascinating and important. But I rather doubt it. And so do Yazdani et al, who rated their confidence in that evidence “low.” (Even though it came from a study they rated as “fair”? Seems like a bit of a contradiction there.)

The review concludes (with some slightly stilted English):

“Shockwave therapy can lead to significant pain improvement, functional rehabilitation, and patient satisfaction with no adverse effect in the management of Dupuytren disease. Pain may return over time, but not to that severity [sic] before the intervention.”

For whatever a small review of a small body of evidence is worth. Reviews are worse than laws and sausages: the more we know about how they’re made, the less we like them (hat tip to Mark Crislip).

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MASSAGE CLIENT: I had an awful time with dry needling. Total waste of cash, just caused a nasty flare-up of pain.

ME: Did you tell your physiotherapist?

CLIENT: Nope. I just didn’t go back. It was so awkward!

It’s astounding how often I have had variations of that talk over the years. But in that case — stuck in my head all these years — I also spoke to that therapist. He told me how his dry needling results were “always” great.

This is a thing therapists do: boast about their “success rate,” as if they can possibly know. They often include some faux humility — “of course it’s not perfect” — to avoid making it sound too good to be true. But it’s always still exaggerated.

Let’s back up a step…

Dry needling review

[Image caption: This post is not about acupuncture, but its weird “mainstream” cousin, “dry needling.” They look identical!]

Dry needling is the insertion of acupuncture needles into sore spots associated with aching and stiffness (“trigger points”). It uses the needles of acupuncture, but not the principles. It is putatively pure biology, but rationalized with hey-you-never-know guesses about how those spots work, and why it might help to “stick ’em with the pointy end” (Arya Stark). Some of the guesses are fairly fancy, but they’re still guesses.

But who cares how it supposedly works, if it doesn’t actually work? The efficacy trials are disappointing reads (e.g. Stieven, Gattie).

Despite the studies, I suspect that some people truly are helped by dry needling — there do seem to be some “strong responders.” But the anecdotes also seem to skew to the extremes, love or hate. The clinical failures tend to be painful, even traumatic.

And mostly unreported.

People don’t like to give therapists bad news

Every therapist who has claimed “great results” for dry needling has probably greatly underestimated their failures. They mostly don’t even know about them!

Patient feedback is minimal at best, and distorted by several social forces and cognitive distortions, especially confirmation bias. Professionals, like all humans, are very strongly inclined to hear only what they want to hear. And clients are notoriously eager to please and often all too happy to tell them! They will bend the truth to make therapists happy, and to convince themselves that their time and money have not been wasted.

Even when outraged, people will still dodge and weave to avoid giving their therapist the bad news. They will even lie.

They tell me the bad news instead. They like telling me.

Every clinician has a nasty problem with “sampling bias” when estimating their own effectiveness. Clinicians simply don’t hear from the unhappiest patients, and from the rest they either hear too much of what they want and too little of what they don’t. Their “anecdata” is hopelessly skewed towards the flattering. (And this is why the whole idea of "intent to treat" exists in research. [1])

And few understand how this works.

Buyer beware of “success rate” claims with dry needling — and anything else.

Dry needling is a topic I’ve written a lot about, but only behind a paywall. There’s a beefy chapter about it in my unique trigger points book — unique because it strikes a rare balance between credulity and skepticism on this tricky topic.

Jono Hey, “Confirmation Bias” on Sketchplanations

[Image caption: Confirmation bias is hard at work in every domain of life, but we are impressively oblivious to it most of the time. It has many effects on healthcare.]

Notes

1. “Intent to treat” is one of those bits of research jargon that makes something simple sound more exotic than it is. It’s really simple idea in principle: one of the main ways that we “control” research is by analyzing everyone that a treatment is intended to help, and not just the people that it actually did help. We want to know how everyone’s results from a well-controlled test — everyone that we try (intend) to treat, succeed or fail. By contrast, clinicians tend to only know about and consider the cases they *actually* (maybe) helped, the success stories — the hits rather than misses.

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Rabies is on my mind after a rare death from the disease in North America: “Brantford, Ontario, area child dies from rabies after contact with a bat, health official says” (CBC). Rabies is notoriously the deadliest of all viral infections, ultimately causing seizures and then paralysis before death — which is thankfully preventable with vaccination before symptoms start, but unfortunately inevitable after that.

Many tens of thousands of people die from rabies around the world every year … but there are only a few dozen confirmed examples of rabies survivors throughout history. Incredible.

[Image caption: An electron microscope image of a rabies virus. Rabies is caused by a number of related viruses in the Lyssavirus family. Image by Norden, a Smith-Kline Company, CC BY-SA 4.0, via Wikimedia Commons.]

The disease is a morbidly fascinating demonstration of how misbehaving muscle can destroy a person. Rabies begins with spasms that define most of its spectacular and distinctive symptoms. For instance, rabies causes opisthotonus, a dramatic backward arching of the entire body, caused by spastic contraction of all the extensor muscles of the neck, trunk, and legs.

The “fear of water” (hydrophobia) and “foaming at the mouth” (just a lot of saliva) is the work of throat spasms. Any attempt to drink or swallow is so painful that the patient becomes terrified of even trying. They drool because they do not dare to swallow!

But it’s even more diabolical than that.

It’s not just drinking that hurts … it’s the thought of drinking. The spasms are caused by a violent exaggeration of the normal reflex that closes the airway to prevent inhaling fluid while swallowing. That airway-closing reflex gets much more powerful and painful and easily triggered — so easily triggered that just the idea of drinking will set it off.

And so — and that horrifying predicament creates the bizarre phenomenon of water “phobia.” The patient suffers from what is surely one of the nastiest paradoxical impulses in human experience: desperate thirst matched only by the desperation to avoid water.

This a disturbing example not only of how powerful and painful spasms can be, but how motivating pain can be — enough to veto one of the strongest physiological needs we have.

Rabies is extreme, and extremes are instructive. There are many more common, milder examples of cramp-powered pain and suffering that are still highly consequential for patients. Exactly how much common pain can be attributed to cramping is perpetually unclear … but it may be quite a lot. See Cramps, Spasms, Tremors & Twitches.

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We do not know for sure that faster and more specific benefits are possible … but they might be. Last week I made the case that exercise is a short term treatment for the much more localized inflammation of musculoskeletal injuries like tendinitis.

What about for pathological inflammation? Like autoimmune disease? Is exercise anti-inflammatory enough for that challenge? We have new evidence that it is.

[Image caption: Cheezy stock photography I wouldn’t buy today, but I did once upon a time… might as well get some use out of it!]

Today’s featured study, by Zhang et al, a Chinese team, is an encouraging scientific review of exercise for axial spondyloarthritis — inflammatory pathology of the spine. This is a whole category of related rheumatic diseases, but it’s mostly about inflammatory back pain and ankylosing spondylitis.

Nasty inflammatory conditions indeed. Although they usually develop slowly and don’t always get serious, this is one of your scarier causes of back pain. No explanation for back pain is definitely preferable to this explanation. I’ve mostly only ever written about them in the context of red flags for more serious back pain.

Zhang et al. reviewed twenty randomized controlled trials of exercise therapy for spondyloarthritis, including 1700 patients, looking at many different outcomes: four different scoring systems, oxygen consumption, and chest expansion (because spondyloarthritis often affects the ribcage), two major biomarkers (C-reactive protein and erythrocyte sedimentation rate), and, last but not least, the two most consistent symptoms of inflammation: pain and fatigue.

That’s ten outcomes, and seven of them improved, most of them quite a bit. That’s a fantastic result! Leading to this unstintingly positive conclusion:

“Exercise therapy is an effective strategy for improving disease control and symptom relief in axial spondyloarthritis.”

So what didn’t improve? Uh, this is awkward…

The two biomarkers for inflammation did not improve — unfortunately. (The other dud was “chest expansion,” likely because it’s a function of irreversible damage to the spine.)

These patients somehow seem to have gotten much better without a measurable anti-inflammatory effect. So what was going on here? How do you get substantial improvements in a disease that is really all about the inflammation … without, apparently, changing the inflammation?

I think the most likely explanation is that the inflammation actually did change — just not in a measurable way.

Justifying the result as “anti-inflammatory” despite unchanged biomarkers

All inflammation is a function of the immune system, but with mind-boggling variety. Immunity isn’t just “complex,” it’s “where intuition goes to die.” It makes rocket science look easy.

And CRP and ESR are rather blunt instruments, notoriously unreliable for diagnosis. Some spondyloarthritis patients never get high CRP/ESR in the first place! And yet no one really doubts that inflammation is still the wrecking ball of their disease. It’s probably possible to get an anti-inflammatory effect rolling without a clear effect on these biomarkers, especially in the short term. And most of these studies were relatively short term. CRP and ESR might well come down in time.

Of course, it is possible that exercise could work its magic on spondyloarthritis without an anti-inflammatory effect, and the lack of a change in CRP/ESR even in the aggregate does point that way. Exercise might protect us from inflammation rather than actually nuking it, for instance.

But we also already have many other evidence-based reasons to suspect that exercise is anti-inflammatory … and here we have a study showing robust benefits for truly serious inflammatory disease! So I don’t think the static CRP/ESR scores are any kind of a deal-breaker.

UPDATE: And then there's this! A fresh systematic review, showing that inflammatory biomarkers are in fact fact reduced by regular moderate exercise.

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A reader asked me how to exercise to reduce the risk of pelvic organ prolapse (POP). Specifically she wanted to know:

“Anything beyond kegels?”

Yes!

POP goes the bladder

POP is the bulging of pelvic organs into the vagina, where they are quite unwelcome. “Heavy lifting” is assumed to be a risk, but — good news — POP is actually not more common in women who lift heavy things, according to Forner et al. Reassuring! The idea that women who lift suffer more POP is at least partly another example of sexist hand-wringing and fear-mongering about how delicate women are.

But there is probably a kernel of truth to it. Light lifting tells a different and informative story …

Forner et al. also reported that women who lift light things reported four times the POP symptoms. 😬 That difference probably shows the effect of doing enough lifting to be a risk, but not enough to get strong enough to mitigate that risk. So the data suggests the possibility that lifting is both the danger and the solution.

Strength probably protects against POP.

“There is more risk for women to not lift heavy.”

Molly Galbraith, author of Creator of the GGS Academy (“Girls Gone Strong”)

So how do you get strong in a way that drops POP risk? Beyond kegels!

Kegels are all about clenching the pelvic floor in isolation, but they are as awkward and tedious as ear-wiggling practice for many, and we don’t even know if they actually prevent POP — there are zero clinical trials. (Hey, science! Study women more!) A fresh episode of Sawbones reviews kegels in detail (medical information + comedy).

But those muscles go to work almost automagically with any exercise that needs core stability, so here’s another hypothesis: the best path to POP prevention is to do whatever naturally engages the pelvic floor muscles.

Like, say, lifting heavy things.

[Image caption: Mariana Molinari decided to get stronger after two years of chronic post-pregnancy back pain, and because she was “leaner than recommended for health.” She knew next to nothing about lifting, and got going mostly with the help of a book, and started to get stronger … and the back pain disappeared! “It was a little weird to see my body change but feeling so strong and so good.” She fell in love with lifting, and especially of “being able to do things I never thought possible.” After many years, she became a trainer so she could help others discover the same thing. “It’s like the prescription that I feel we all need to keep up with life. I can do things at 56 that I couldn’t do in my 20s.” You can do online training with Mariana at Strength Sisters 101.]

Carefully at first, of course! And not just on general principles, but specifically because the trick is to get through early training without getting hurt — if we can trust our science clues.

It’s all about baby steps, of course: you train for any challenge with simpler, tamer versions of it. For example, to prepare for a big dose of fall firewood-schlepping, start in the summer with kegels and easy, tidy squats and deadlifts (stooping lifts), which challenges some of the same muscles in a tidier way, safely toughening you up until you can easily oomph your way through exercises that approach the challenge of, say, moving a big pile of firewood.

There is no “evidence-based” POP prevention protocol, but I do think this is a science-informed strategy.

More photos of real women who lift really heavy things

Last week I introduced a new compilation of photos of very un-fragile "real" women doing assorted powerlifting and weightlifting exercises — not stock photo models. Most of them are subscribers, many work as coaches and trainers, and they are all living, breathing examples of how strong women can be.

Here are the rest of the photos I’ve collected so far. They are also now all featured in my main article about strength training, which has been updated a bunch recently.

[Image caption: Kelly Lobgeier started lifting quite young, but dropped it for many years when she started a family — the reverse of several other stories here. But she missed the lifting! “I’ve always been a huge fan of weight training, and boxing.” When she returned to the sport at age 42, there was no stopping her: she quickly ramped up from three days a week to five, then found a coach, and then went on to compete in four bodybuilding shows in three years. “That process taught me how important diet is for body composition, and the importance of pushing your body to certain limits.” She has been a personal trainer since 2019.]

[Image caption: Lois Smith is one of many who came to lifting via CrossFit. She started after the birth of her second son, to “rehabilitate my core” and “now it’s a way of life!” Her lifting is often featured on her Instagram @lois_smithy.]

[Image caption: Rachel Moore has been lifting for about six years, and considers it "a form of mental therapy, getting into my body and out of my head." Her advice to beginners is to find the right gym or even community to guide them at their own pace. “I’m group oriented in my exercising so I like having a coach and people around me doing the workouts together, it helps me stay motivated!”]

[Image caption: Stephanie Fraser (Instagram @stephanie.fraser) started her “fitness journey” after having her first son in 2008, but it wasn’t until she started training and coaching that she started to “lift to get strong” and “fell in love with powerlifting and the training involved.” Now she trains in Olympic lifting and coaches powerlifting. “As with any sport,” she’s had some injuries. “That taught me a lot about patience, my own mortality.” Her advice for women is “always this: lifting can help you feel powerful which will give you a mental boost like nothing else. Plus it can provide a healthy outlet to constructively cope with the emotional labour we typically struggle with as women. It will help you with the much-needed bone strengthening and mitigate muscle loss we face as we age, allowing us to keep our independence more effectively.”]

[Image caption: Tara Hawkin (Instagram @taraatthebar) has been lifting for about a decade, and says she’s an exception to the rule that it’s hard to get “too bulky”: she “looks at a weight and puts on more muscle!” She’s dodged any significant injury, but her back gets “cranky for a few days” after a lot of snatches or deadlifts. “Lifting with your ego is usually a pretty quick way to get injured,” she says, and recommends “gradual progressive overload with some weeks off thrown in.” Like seemingly every woman who lifts, she loves “the empowerment angle” and feeling “I walk through the world with a confidence that I may not have if I didn’t have these boulder shoulders. They’re great for carrying my child and also for making only one trip up from the car with all the groceries!”]

[Image caption: Terri Rowan was aiming to deadlift her bodyweight when this photo was taken. “I don’t know why I chose that number, it just seemed like a good number,” she says. “I got to my goal pretty quickly.” Why does she do it? “I legitimately get enjoyment out of lifting heavy things. That enjoyment is probably a swirling mass of lots of things: chemical (endorphins), a sense of achievement, etc.” But also the big reason that seems to be shared by most women weightlifters: “as female identifying I think it is also just badass to be able to lift heavy shit.” Her advice for beginners is “Don’t let perfection be the enemy of progress. We won’t talk about how long I debated with myself about what combination of plates to buy when I set up my home gym. But I finally just bought some, and guess what, they’re still the same ones I use! Don’t complicate things.”]

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Bliddal et al., New England Journal of Medicine

These drugs reduce blood sugar and treat obesity, with a variety of downstream benefits that are still being studied. Add “great for arthritis” to the list. How does that work? Asaf Weisman (in the comments on his post):

Belly fat is active tissue that secretes adipokines and other pro inflammatory agents which contribute to epigenetic changes that accelerate tissue degeneration.

We’ve had many reasons to suspect this for a long time, but this is a good quality placebo-controlled trial of an effective weight loss drug in humans, and so it’s case closed: lose belly fat, hurt less.

I do worry that this evidence could inspire excessive “just lose weight” advice, justify fat-shaming, and result in misplaced blame on loading (wear and tear) instead of metabolism. The “just” part of “just lose weight” is just wrong! There’s nothing “just” about losing weight.

But if this is actually how things work, then we must just forge ahead as best we can: education, education, education! At least this gives us a strong evidence-based direction to go. This study probably deserves another more detailed post in a while.

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Can you help an overwhelmed tendon by using it more? In the short to medium term?

Many people ironically overuse an overuse injury, while others fear wear and tear too much. Those extremes may obscure a valuable sweet spot in the middle, and that is what the science hints at so far. This post explores that possibility in detail, with particularly thorough referencing, especially for the critical premise that “running doesn’t cause arthritis.” (And see also a closely related follow-up post: STUDY: Exercise eases inflammatory back pain—but why?)

[Image caption: This fact has now spent many years on my top 10 list of things that huge numbers of people still don’t know, but should. If you’re going to believe that exercise is medicinal for joints and tendons, you have to start by accepting that it’s not harmful.]

---

Uwe Kils & Wiska Bodo, CC BY-SA 3.0

Today’s members-only post is about 1400 words, or a 5-minute read, and it includes a chatty audio version. There’s also three times that much content in the footnotes: nineteen relevant studies, all with thorough high quality, readable summaries.

My footnote game is strong in this post. But no, I don’t read all the footnotes in the audio version. I am thorough, but not cruel.

Unlock the post by becoming a PainSci member.

Membership starts at USD $3/month for “good” PainSci membership, which will get you all the exclusive emails (the main benefit) … or go “better” for $5/month to unlock more perks (audio versions, post archives, members-only content on the website, and more) … or try “awesome” for $10/month to unlock … um, not much more. 😜 (That top tier is more about just supporting independent health science journalism. Which many beautiful people do!) Compare plans.

The salamander’s domain is for people who are serious about this subject matter. If you are serious — mostly professionals, of course, but many keen patients also sign-up — please support this kind of user-friendly, science-centric journalism.

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Nothing in life is perfectly safe, but lifting heavy things is safer than most people assume. Even the heaviest things, as in bodybuilding and powerlifting. And even for women.

Sports science is full of the idea that women are more structurally and/or physiologically vulnerable and get hurt more. (White women, that is. Black women are perceived veeery differently. Spoiler alert: it’s not an improvement.) This sexism is more plausible in some cases than others, but mostly it’s just an obnoxious vestige of the more overt chauvinism of the past. A dramatic re-enactment of the evolution of the myth of feminine fragility:

Olden times: “Ladies in athletics? Ho ho, don’t be absurd old chap! Ladies are not designed for the manly arts. If God wanted the fairer sex to be sporting, He would have made them as tough as old boots. But then who’d want to marry them? Har har!”

Today: “Women can be fine athletes, but obviously they have some more injury risk factors because of their biomechanical idiosyncracies. Tsk tsk!”

There are some aspects of female anatomy and biology that are legitimately risk factors for certain injuries. For instance, women are going to sustain more “frictional breast injuries.” Pelvic organ prolapse is a problem that's unique to female anatomy (see my follow-up post about that, Q&A: Beyond kegels for pelvic organ prolapse prevention).

But of course men also have unique vulnerabilities! Google “twisted testicular appendix,” if you dare. (I have personal experience with that one!)

Bottom line: There is no major difference between the athletic vulnerabilities of men and women.

[Image caption: Chrystal Ladouceur is a Registered Massage Therapist who lifts and coaches. She started lifting in her mid-30s. “Before that, I drank a lot, smoked a lot, and spent most of my time sitting around. I’ve come a long way, even with such a late start. It’s never, ever too late to begin. My only regret is not starting when I was younger.”]

A pitch perfect example: “women do not heal”

I posted recently about women doing deadlifts, and a medical doctor replied:

"Please, no! The discs in women do not heal."

Really?! Citation needed … badly. Intervertebral discs can heal poorly, but equally so in men and women as far as I know. I replied:

“If you are going to try to make the case that women specifically are too fragile for heavy lifting, you are going to have to bring your science A game … and good luck with it.”

His only answer wasn’t even relevant.

More photos (and inspiring examples) of women who lift heavy things

I only wanted one photo of an un-fragile woman lifting a hefty barbell for this post, but I didn’t want a stock photo of a model (often the best I can do, especially on short notice). So I asked if any of my readers were “women who lift heavy things” and would be happy let me use a photo.

As the photos flooded in, I realized there was no way I could use just one. I’ve picked fourteen.

These are not all high quality photos, which is deliberate: these are real women lifters, not models, and mostly not pros or elite competitors (although a few are).

All the photos are used with the permission and collaboration of the women shown. I’m sharing about half of them here, and I’ll include the rest in another related post soon. They are also now all featured in my main article about strength training, which has been updated a bunch recently. Weightlifting deserves more attention, especially for women, because its health benefits are truly impressive.

[Image caption: Cara Bereck Levy is sixty-two and a grandmother, and she tells me that she started lifting “when I realized I might have to grab a grandchild and run to the bomb shelter.” So that’s one hell of a reason to want to be stronger! Here’s her (public) Facebook post with more information.]

[Image caption: Elaine Robertson in her garage gym in Beith, Scotland, where she’s been lifting for about a decade. Her husband runs a strength and fitness coaching business (Instagram @strengthforhealth), and he got her into the sport after she finally overcame the objections many women have, like the “wildly-overstated risk of becoming bulky.” But now she can “blithely carry fully-laden suitcases up flights of stairs” and, much more importantly, “lift my 82 year-old, frail, osteoporotic mum after a fall from which she was unable to get up. A key driver for my strength training is avoiding following her into frailty.”]

[Image caption: Giusi Protopapa (Instagram @protopy____) started CrossFit in 2019 “almost by accident” while looking to improve her fitness. Now she’s working out at least four days per week. “That time dedicated solely to myself is sacred; by the end of each workout, I come home more tired, but undeniably happier.” Worried that lifting will make you less feminine? “The essence of being a strong, feminine woman is self-assurance!”]

[Image caption: Jennifer Adams (Instagram @best_life_bits) is a massage therapist who had been lifting casually for years before she kicked it into high gear in 2021. She dove into the deep end at a gym most women would have been wary of: all men, all serious. But she forged ahead, guided by YouTube. What kept her going? “I feel less tired at work. More confidence in moving heavy things. I look better.” She actually tried hard to get bulky, and failed: “My muscles look more ‘toned’ after a few years lifting heavy than all those years of lifting high reps and making cardio a priority.” Interestingly, the male-dominated gum was “freeing” because “there’s no judging if you grunt or strain or fail.” She has many clients that she believes could “improve or cure their aches if they worked out.” And there’s the bone density benefits regardless!]

[Image caption: Jesse Robson started lifting when she began training to be physiotherapist (clinic in Bridgewater, Nova Scotia, Instagram @live.well.physio). “I never wanted tell someone else they ‘should’ be doing something (e.g. regular resistance exercise) if I wasn’t willing to put the time and effort into doing it myself.” She’d had chronic pain for about five years before that, and thinks lifting played a significant role in her recovery. “After deadlifting 200 lbs, it seemed far fetched that my body might be damaged, broken, or unstable.” If you’re wary, she’d love you to just try it out. “I have the impression that many women are proud to have overcome sexist stereotypes related to heavy lifting (“let me get that for you honey”) and enjoy showing that they can lift heavy things!” But it also might “dramatically improve the last 10 years of your life. And best of all, you look cool doing it.”]

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When we’re in pain — because of an injury, or who knows why — we want something that will reduce the intensity and duration, and we would be happy to pay whatever we can afford for that result.

Or more than we can afford.

And so there are countless services, products, and ideas that make that offer in one form or another. Supply for one of the most potent of all demands.

Which is why you’ve mostly only ever heard of bullshit treatments and therapies for pain — because they exist to improve someone’s bottom line, and only the sexiest and simplest ideas can compete in that valuable marketplace. Only the ideas that are the best at convincing you to open your wallet have survived to become known. They have outcompeted a thousand others by virtue of aggressive promotion and/or by being simplistic and emotionally appealing enough.

The point 👉🏻 It’s impossible to overstate how much marketing, hype, and clickbait have defined pain and injury treatment.

This has been happening since the patent medicine era, more and worse with every decade. No bad idea ever dies — not if you can still sell it! The grift goes on and on.

[Image caption: An example of a well-marketed product that I bought despite my cynicism]

[Image caption: This stuff is just another form of spice therapy, “Tiger Balm” sold with the “ancient wisdom” of Native Americans instead of the Chinese. I think it’s ridiculous, probably even offensive … but I bought it! Partly so I could honestly claim to have tried it for a writing project, but also because I have pain to treat and — yeah, I admit it — the excellent packaging got me. I am a sucker for good quality typography, design et cetera … but literally everyone is, because this stuff works on us even when we are cynically aware! But you know what does not work? The one active ingredient here: capsaicin. This product category has been a best-seller for centuries because it has a trivial but very real effect on pain … which makes it really easy to sell. Even to me! 😜]

What happens to the good ideas?

Good rehab and pain medicine mostly gets drowned out. It isn’t branded or marketed, because it’s too complex and nuanced. It literally requires humility, comfort with uncertainty, and critical thinking skill (and thinking critically is a skill). It’s both nerdy and emotionally mature.

And so the good stuff cannot be bottled or packaged, and defies easy definition and standardization. The power to deliver it cannot be had from a workshop; no school (or school of thought) can consistently produce practitioners that good, not even close.

And all of that practically guarantees the rarity of one of the few things in this business that is actually helpful to patients in pain: a competent and compassionate guide and troubleshooter, with a ton of knowledge and a good bullshit detector.

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What if you could treat chronic low back pain just by teaching people that it doesn’t actually have much to do with whatever’s going on with spines? That it’s more a matter of pain getting wound up by fear, anxiety, exhaustion, and immobility?

Could just understanding do the job? It sounds a bit implausible. No one doubts that it’s helpful in various ways to be well-informed about a diagnosis, but it seems like a bit of a reach that it would be properly medicinal.

But that is the big idea of “pain neuroscience education” (PNE), one of the hottest hypotheses in the modern rehab business (see Mind Over Pain). There is a modest body of evidence on this topic, pointing every which way so far.

Kayode Eyumi as Roll Safe in “Hood Documentary.” (No, it’s not Eddie Murphy.)

A PNE test

Adenis et al. is a new direct test of the effect of PNE compared to more conventional education. They studied 88 middle-aged patients, 60% women, with year-old low back pain. Everyone did a multidisciplinary rehabilitation program (MRP).

Half added old-school “back school” education to their MRP, doubtless thrilling stuff: knowledge bombs about “spinal physiology” and ergonomics and the hazards of poor posture. If this combo was a meal, it would be fried eggs, limp bacon, and greasy hash browns. It’s not clear that it would be nourishing at all.

The other half got PNE with their MRP: “I’ll have the smoked salmon eggs benny.” And they got plenty of it: eight 30-minute sessions. Although the one-week duration could be considered a weakness, surely PNE can work its magic in four hours of indoctrination in a specific way of thinking about back pain. Surely?

The objective was to help the patient understand that their pain was related more to neuro-immune sensitization (maintained by multiple modifiable biopsychosocial factors, including perceived threats) than to the health of their tissue … Visuals and educational content were closely based on the following PNE media (amongst others): Explain Pain (Butler and Moseley, 2003), Everyone has Back Pain (Louw et al., 2015), Recovery Strategies (Lehman), and Retrain Pain (Retrain pain).

The authors assumed that PNE would be better, and so my hats off to them for honestly reporting what must have been a disappointing result.

PNE didn’t win

PNE was ever-so-slightly better, but the difference was “not statistically significant.” Everyone got better, of course, because back pain studies always show groups of people drifting in the direction of recovery — but there was no real difference in how fast or far they drifted.

The results of the present study of an MRP did not demonstrate a statistically significant difference between … groups with regard to various outcomes, including pain, fear-avoidance beliefs, catastrophizing, kinesiophobia, anxiety, and depression.

I think the most glaring flaw here is that PNE was somewhat at odds with the very typical rehab program that everyone did, contradicting it in some ways rather than harmonizing with it. They researchers made some effort to tweak the MRP so that it was less of a clash, but still … maybe the result would have been different if the PNE group had just gotten PNE.

Or maybe not. Because PNE is always superimposed on a background of more conventional rehab ideas — they’re impossible to avoid! So this way of testing it is realistic instead of ideal.

This isn’t a last-word study, not by a long shot, but it’s certainly a discouraging word for PNE fans. But patients with stubborn chronic pain are not PNE fans.

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Speaking of lifting things, to get this party started …

An example of minor disability from pain

I cannot currently lift even one end of my lovely e-bike.

I love my my “wheelchair,” a cool tool that I bought in 2023 to help me stay active and mobile when chronic illness is chipping away at what I can do. It has helped me reclaim a little youth. I don’t even use the motor all that much; it’s been amazing how much more I’m willing to do under my own power when I know that I’ve got a great motor as backup.

Unfortunately, storing expensive bikes in tiny, overpriced Vancouver apartments is a real challenge. Every centimetre counts, and this thing nearly doubles its footprint when it’s leaning over on a kickstand.

I need a wall mount, I thought. I’ve always wanted to hang a bike on the wall. It’s time.

But… if I cannot even lift a pot or pan without strong pain … and I cannot lift my bike anymore! And it’s not because I’m too old or weak. It just hurts too %@&*# much!

My right elbow and forearm are in some kind of trouble. It’s painful to pick up a pot, or even squeeze an earplug. I’m strong enough in general, but my grip is the very weak link. I could barely get the front of the bike off the ground before I had to let go.

A strange elbow

My elbow has been slowly worsening for about a year. It was just an erratic annoyance until the spring of 2024. Since then it has steadily ramped up, becoming intense and stubborn even by my rather exotic standards. Because of my health issues, I’ve had some some chronic pains that were whoppers, but this is the whopperiest so far.

Originally the pain seemed like elbow arthritis: morning aches in the joint. Over time, it spread into the forearm and started to seem more like an odd case of tennis elbow.

Tennis elbow is an overuse injury, a tendinitis of the common extensor tendon where all the muscles of the forearm converge on the outside of the elbow. But some things about the diagnosis don’t fit well at all:

1. My worst pain feels like it’s right in the bone and joint of the elbow itself. That is definitely the epicentre of the discomfort.
2. The pain spreads from my elbow into my forearm, but largely leapfrogs over the CET, which does not particularly hurt at all. So my secondary epicentre is about a third of the way down the forearm in the muscles.
3. This problem isn’t actually much bothered by the things I do the most — like typing, fortunately — which isn’t very much like an overuse injury.

When things first got bad, I just tried to “take it easy,” my reflexive response to any new pain, and especially one that might be related to repetitive strain. But it just kept getting worse! So …

I decided to do more of what hurts

To fly right into the storm. Maybe the way out is through. I would overuse my overuse injury … if that’s what it is.

Lifting pots and pans has always been nasty, so pots and pans became my forearm barbells: lifting them like a cook slowly flipping a pancake, over and over again.

My plan seemed foolish, so I took it slow at first. It would hurt like hell for the first few lifts, then ease … and ease some more … and then I could continue without any pain at all. Amaze! (In the novel Project Hail Mary, Rocky the alien rock-spider says “Amaze!” when he’s amazed — and now I do too.)

Two hours after lifting pots, I could still pot-lift painlessly. Amaze amaze amaze!

I was doing what seemed like the worst possible thing to do, but it felt like the best. Yahtzee?

Nopezee!

Like Groundhog Day for chronic pain

My elbow challenge gets a reset every day. The pain always comes back within a few hours, and usually worse.

I can always beat it back with more pot-lifting — but less effectively each time, and it’s futile late in the day.

Then things calm down while I sleep and it starts all over again.

The analgesia I’m getting from doing the most painful thing I can think of is real and substantive, better than anything I have gotten from ibuprofen or Voltaren, icing or heating or both (contrasting), stretching, massage therapy, spicy ointments, and more. I’m slowly working through all the options (with very low expectations).

After many weeks of pot-lifting, I think it’s safe to conclude that it’s (a) very useful, but (b) also not actually solving the problem.

Why do I get such strong relief from something that is so painful at first? Why would anyone? We all wish I could explain that. And I could speculate for 2000 words, but it would be a poor value, just a wordy version of “I really haven’t got a clue.”

Ever had a pain that was eased (and quickly!) by doing whatever hurt the most at first? Reply with your story, or put it in the comments on the Facebook post.

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As of 2024, the most recent scientific review of running injury prevention is thirteen years old. It was a garbage-in-garbage-out review of “very weak” trials … telling us little.

A new study by Leppänen et al. gives us a refreshing change, but it directly challenges one of my strongest biases: I don’t think hip strength is important for runners! (I think strength is important for runners, just not the hip/core particularly.) I won’t be changing my mind based on evidence from one study, no matter how cromulent it seems … but it does seem good. They begin by acknowledging that “the evidence is still very limited” for exercise-based injury prevention in novice runners. And that is clearly what they are trying to fix. One of the authors, Dr. Benno Nigg, is a particularly trusted source for me.

And its conclusion is clear: Paul was wrong.

I hate it! I love it! Bring it on.

[Image caption: How to prevent common running injuries has been one of the great mysteries of sports medicine — possibly now solved?]

The study design: core vs. foot vs. stretch

I believe that the importance of core strength has been overstated for decades. Hip strength for runners is a closely related idea, based on even less evidence, and I have a whole article that heaps scorn on it. The burden of proof was always on fans of core/hip strengthening, it has never been met, and the whole line of thinking has major problems.

To try to answer this question properly, Leppänen et al. studied 245 novice runners in Finland for several months in 2021 and 2022, doing twice weekly group runs and training sessions, from May to October each year. The science sorting hat was used to put them into three test groups:

1. Hip and core exercise.
2. Ankle and foot exercise.
3. Static stretching for a control. (Because it’s considered useless for prevention, LOL.)

Training sessions were led by physiotherapists and consisted of “common physiotherapy exercises,” bog standard stuff, nothing fancy, but certainly a decent general workout for the hips and core (details). Participants did an extra weekly session or two on their own, tracked by a gadget, and filled out weekly surveys. Everyone did general warm-ups before runs, plus their specific program.

The researchers tallied up every kind of lower extremity injury that happened, and also filed them into categories like overuse (runner’s knee), acute (ankle sprains), and severe (losing more than week of running).

The startling results

The risk of any kind of injury was reduced by about a third in the hip and core group compared to the stretchers. Results were a little better for overuse injuries, and better still for more severe injuries.

(The foot group was identical to the control group for overuse injuries, but had a crazy 3.6× higher rate of acute injuries. We could have a whole conversation just about that! What the hell, foot folks?!)

The most important finding of our study was a 39% lower prevalence of all injuries and 52% lower prevalence of substantial overuse injuries in novice runners performing hip and core-focused programme compared with group performing static stretching before running.

Mic drop? If this study is right, then I have been wrong about this for many years.

There are a lot more details, and they are good details. I’ve read the whole thing carefully and suspiciously, and no problems jumped out at me. I could “nitpick,” and there are acknowledged limitations — there always are — but basically this seems like a solid experiment.

Some reasons for a little skepticism

1. Just one study! Even a perfect trial can give us the wrong answer by fluke alone. It could be an outlier, and it’s easy to imagine it looking that way next to future experiments.
2. A 50% drop in run-stopping injuries is good but not great from every perspective. Some people won’t think it’s worth adding a lot of exercise to their exercise. “You mean I have to run and do a lot of leg lifts and crunches… to make it somewhat safer?”
3. Just because core/hip strength did quite well here doesn’t endorse them for other goals, like preventing or treating back pain.

Nevertheless, if this is replicated, I will eat my humble pie. Nom nom nom. I pinkie swear.

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CRAZY Barbershop Therapy fixes 20 YEARS SHOULDER PAIN  16:09

This infamous video showcases a dramatic form of spinal “adjustment” with a hammer and blunt “chisel,” and the crazy is right in the title: “CRAZY Barbershop Therapy fixes 20 YEARS SHOULDER PAIN.” If you can’t spare 16 minutes for this gem … after a good spinal thwacking, the patient can finally lift his arm. Raparo! 🪄

If nothing else, this is an amazing example of social media algorithms favouring extremes: 12,000,000 views, 135,000 likes, 6,600 comments. That’s engagement on a scale no thoughtful analysis can come close to matching. Impressive! And depressing.

Chiropractic? That’s up for debate, especially because it closely resembles Thai tok sen massage, but it is indeed perpetrated by a chiropractor, and the intention of what he’s doing is “adjustment,” very chiropractic-in-spirit — exactly what people think chiropractic is about, whether they should or not. More below on what this technique actually is.

Can it possibly be effective, whatever it is?

If it’s not just faked, like a faith healing, then it is still excellent “therapy theatre” — whipping up a good batch of placebo analgesia with strong story and sensations. The video charismatically and competently sells the concept to both patient and audience. This comment captures the simplistic appeal:

“I need someone to bang on me with those tools, like I’m a broken down Chevy.”

Honestly, I get it. There are days when I want the hammer treatment too. Which raises some awkward questions.

Is therapy theatre therapeutic?

If you can persuade a nervous system to do this, even temporarily, isn’t that a good thing?

I am torn, because this hammer business is probably just a more dramatic and stylish way to deliver exactly the same non-specific active ingredients that are the reason so many of us enjoy manual therapy … and not for nothing. Maybe it can create “window of opportunity” for improved recovery. And maybe a sensation-enhanced placebo can be dialed up quite far.

But I also don’t “want to go to there” thanks to a nonsense narrative about what’s going on! Among other aesthetic turn-offs.

Many studies have shown that spinal manipulation does not work well … not even for back pain (let alone shoulder pain). Placebo analgesia is notoriously minor and fleeting, which is (partly) why it’s unethical to lean into it. So this line of inquiry generally leads straight to that ancient mystery: is it okay to prescribe placebos? Mostly no, “officially”: the medical ethics have always been pretty clear that baffling people with bull is not cool … and that goes double when it’s also used as marketing.

So I think this is more like theatre than therapy. Faith healing is the most obvious comparison, but maybe stage hypnosis is better: a weird phenomenon, but no one is really being “controlled,” anymore than anyone is being “healed” with hammers. The video is entertainment — not video documentation of a secret weapon against pain that only manly chiropractors have figured out.

Jono Hey, The BS Asymmetry Principle on Sketchplanations

[Image caption: Sharing this here for no particular reason …]

Chiropractic or massage? (An addendum a week after publication)

The technique in the video closely resembles a form of Thai massage, tok sen, which uses a wooden mallets and wedges of various shapes. Despite that resemblance, it is also thoroughly chiropractic in character.

Tok sen could also be called “hammer acupunture,” because (of course) it is based on the vitalistic concept of restoring the normal flow “energy” — exactly like acupuncture and traditional Chinese medicine. But don’t make the mistake of thinking that this means tok sen has nothing to do with chiropractic! Because chiropractic is deeply rooted in energy medicine. A century ago most if not all chiropractors assumed that they were manipulating spines to restore “energy” flow — not making much distinction between “energy” and “nerve impulses” — and modern chiropractic is still rotten with vitalism (especially Applied Kinesiology is Bunk, a chiropractic favourite).

Banging imaginary points and pathways by any means also looks an awful lot like the chiropractic “activators” — a little tool that looks a lot more modern and medical but is barely different in principle, simply delivering a little tap, and for all the same reasons. So tok sen, despite usually being described as “massage,” is right at home in chiropractic. It may not be what good chiropractors do, but it is most assuredly something many do, for the same kinds of reasons as they’ve ever done anything.

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1. Finish recovering from Covid #3. 😠 Having Covid isn’t newsworthy anymore, but it can still really pack a punch. Indeed, it’s busily murdering a lot more people than flu (mostly the unvaccinated). My third case has been mild, but I am exhausted.

2. Finish a master plan to build a stockpile of fully prepared posts, with big benefits for content quality, consistency, and my sanity. I’d like to feel prepared, organized, and un-hurried for the first time in three years! But, ironically, I’ll have to rush even more to achieve this. For a month, I’ve been writing twice as many posts as I’ve published, and I’m getting close … but I need a break from publishing to get it done without breaking something. (Especially given the Covid!)

So, thanks for your patience while I take a breather. I know it’ll be tough, since there’s nothing else to read, learn, or be amused by out there. 😜

Speaking of other things to read, I’ll leave you with this painful quote I just found in Hugh Howey’s “Silo” novels. I’ve been listening to the audiobooks, and also watching the show, starring Jessica Ferguson. This passage about muscle and pain jumped out at me:

She sat down and rubbed her legs, her thighs and calves tight from the most recent hike up. She may have been gaining her porter legs these last weeks but they were still sore all the time, the ache in them a constant new sensation. Squeezing the muscles transformed that ache into pain, which she somehow preferred. The sharp and definable sensations were better than the dull and nameless kind. She liked feelings she could understand.

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A couple times a year we see headlines about thrilling advances in the war against pain. Scientific American: “New Painkiller Could Bring Relief to Millions—Without Addiction Risk.” The article strongly implies that VX-548 is a major upgrade, more powerful and less addictive than opioids.

That’s … unlikely.

And I am always preemptively underwhelmed by these stories, and irritated by their predictable format:

• Give pain a face! “When doctors ask Sara Gehrig to describe her pain, she often says it is indescribable.”
• Elevator pitch for how it works: “Blocks pain signals before they can reach the brain. It gums up sodium channels [NaV1.8] in peripheral nerve cells … because the drug acts only on the peripheral nerves, it does not carry the potential for addiction.”
• “Promising results” are cited, FDA approval is pending, and the manufacturer is named (because the article is just a dressed up press release).
• Obligatory paragraph of horrifying stats about chronic pain.

Like fusion power, safe and strong pain-killers have been thirty years away for decades, because there are basic reasons in principle why killing pain is hard. Pain has many possible causes, and it’s so integrated into our physiology that it’s nearly impossible to mute without also disabling critical subsystems at the same time — which is why .

And the VX-548 data to date can already curb your enthusiasm: it beat a placebo for acute post-surgical pain, but … only in high doses … and it “did not beat a cheap, off-patent opioid-based regimen in either trial.” A disappointment strangely neglected by the press release!

It is cool that this drug targets peripheral nerves. If it actually works about as well as hydrocodone, but can’t be abused, it may yet be a big deal.

But it probably won’t be cheap, and therefore accessible — how could it be? A major investment must be recouped! And it isn’t obviously a game changer that will “bring relief to millions.”

No one believes hype in headlines anymore, though… right?

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Sixteen years seems like a long time to wait to criticize a study.

For nerdy fun, today’s members-only post explores the highlights of a new exchange of letters debating “concerns” about an experiment from … 2008! Shah et al. published particularly interesting evidence about the etiology of trigger points, reporting that they are “toxic” — acidic and sloppy with waste metabolites — which gave some support to the controversial “tiny cramp” hypothesis of sore spots.

It was easy for skeptics to dismiss this as “just one study, and an error-prone one at that” back then, but Albert and Moraska waited until now.

Was their letter better late than never? Or just late?

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Were you taught that if you contract your quads in a forward fold, this will relax your hamstrings because of “reciprocal inhibition”?

Word to the wise, science-based yogis: this idea has been outdated by research for over 15 years! 🤯

When we contract a muscle in a stretch, the opposing muscle doesn’t relax.

Actually inhibiting the opposing muscle (antagonist) would get kind of sloppy, like a tug-of-war team that falls when the other team just lets go. The reality is more like an agreement by one team to lose — but not too badly. Contraction is a balancing act, where one muscle contracts less but still maintains tension.

Which is doubtless vital for evolutionary fitness!

[Image caption: If your quads are shortening, does your nervous system order your hamstrings to relax? To “inhibit” them? This popular idea is probably wrong.]

Reciprocal inhibition has been one major premise for proprioceptive neuromuscular facilitation (PNF), the main fancy alternative to lowly “static” stretch.

Up to 2009, the literature had been back and forth on reciprocal inhibition, with a few “no” experiments, like Osternig and Condon, and some “yes” tests, especially Etnyre, who claimed (back in 1988, in the Triassic Period) to resolve the conflicting evidence by showing that you can measure reciprocal inhibition if you just use electrodes stuck deep in the muscle, rather than mere surface electrodes. But Mitchell et al. weren’t satisfied, did a more meticulous experiment, and “did not observe reciprocal inhibition using surface or wire [deep] electrodes.” Womp-womp.

The findings of multiple researchers that a muscle’s tone increases during its antagonist’s contraction seems to be validated by this study. Neurophysiological factors such as reciprocal inhibition and autogenic inhibition appear to not be responsible for the higher ROM gains achieved through PNF stretching.

And just nothing since. Argument over? That detail might be settled. But note that it’s no longer even clear that PNF produces “higher ROM gains” by any means, let alone reciprocal inhibition! See Hill or Lempke.

As usual, stretching is bit of a nothing burger.

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There’s a vast gulf between what kids and olds can get away with eating. And in the oldest of the old, a lousy diet is linked to fatigue (Davis, Azzolino), and that vulnerability of the elderly is an interesting clue that junk food might cause fatigue for more than just a few hours of strained digesting after a reckless meal.

Another clue: there’s some evidence that junk food is a medium-term risk factor for pain. It was a bit startling to see evidence that a poor diet might inflame pain in just weeks or months. Could the same be true of fatigue? A reader asked, and then I wanted to know too.

I haven’t been able to find clear evidence of this, but it is highly plausible in broad strokes. Pain and fatigue have a lot in common physiologically, probably mostly through the shared mechanism of inflammation. There is a mountain of evidence that poor health is both fatiguing and painful on a timeline of years.

But is any diet junky enough to cause fatigue beyond the acute effects of straining to digest it? If a healthy person starts a junk food diet in August, will all their days be more fatigue-filled by Halloween?

And could the “ultraprocessed foods” in particular do this? They may be extra “proinflammatory” (Asensi), and they are probably linked to depression and anxiety (Hecht), and even cognitive decline (Bhave) — though it’s unclear if they are causally linked. (The UPFs are also a magnet for profitable fear-mongering, and they may well be guilty only by association with the many other health headwinds in people who live on instant noodles.)

Whether junk food acts like a mildly exhausting poison in otherwise healthier adults remains unknown. But it does seem likely.

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