• Good advice for aches, pains & injuries

Massage Therapy Side Effects

What could possibly go wrong with massage? The risks and side effects of massage therapy are usually mild, but “deep tissue” massage can cause trouble

Paul Ingrahamupdated


People think of massage therapy as a “safe” therapy, and of course it mostly is. But things can go wrong, or at least a bit sour. While serious injuries in massage therapy are extremely rare, the cases that are diagnosed and reported in medical journals are probably outnumbered by less dramatic examples. And minor side effects are downright common. A 2007 survey of 100 massage patients1 found that 10% of 100 patients receiving massage therapy reported “some minor discomfort” in the day following treatment. This would mainly be a familiar slight soreness that is common after a massage, known as “post-massage soreness and malaise” (PMSM) — and I’m surprised only 10% reported it. The massages they were getting must have been quite gentle.2

Interestingly, 23% reported unexpected benefits that had nothing to do with aches or pains. (Benefits for musculoskeletal problems were not documented.)

This study is underpowered; it cannot and does not rule out rare and/or serious side effects of massage therapy, which do exist. You could probably do several studies of 100 patients without encountering a single nasty situation. But what if you surveyed 1,000 patients? Or 10,0000? Massage is not completely safe — what is? — and other adverse effects would almost certainly turn up in a big enough survey. Nevertheless, according to one of alternative medicine’s most vigorous critics, Dr. Edzard Ernst, “Serious adverse events are probably true rarities.”3 And yet, reviewing the literature again in 2013, Ernst and Posadzki found at least 18 reported examples of “moderately severe” reactions to normal massage, especially of the neck.4

When massage goes bad

So what could possibly go wrong? Massage can …

A little more on that last one: I’ve seen many patients unwisely prioritize massage over medical care, and way too many massage therapists who went along with it and missed the medical significance of serious symptoms, overconfidently attributing them to something like “toxins” or “cranky muscles.” Massage therapists are prone to pseudoscientific beliefs,6 and appalling diagnostic ignorance is probably the most dangerous thing about massage therapy, as with all alternative medicine.7

In my decade (2000–2010) as a massage therapist, I met many patients who had been harmed by massage therapy one way or another — fortunately, mostly just expensive disappointments and minor backfires, but quite a few more serious cases too.8

Sensory injury from painful massage

One of the first massage clients I ever had started our relationship with this warning:

My last massage therapist ruined me. I do not have a high pain tolerance. I begged her to be gentle, she ignored me, and I winced and sweated through the whole experience. I felt awful, and I’ve never been the same since. I feel like it ruined me. That was a year ago. I’m here for a gentle massage. If you aren’t gentle, I will get off the table and walk out the door without paying you.

I was gentle, and she was a regular client for the rest of my ten-year career. She was probably my first clinical example of “sensory injury,” years before I thought of those words. My reputation for being a gentle therapist started with her, and led to me becoming the go-to therapist for patients who were “refugees” from intense massage. I have been paying attention to this topic for 20 years now.

A painful, alarming sensory experience can actually dial up pain sensitivity — even long term.9 Furthermore, vulnerability to this awful phenomenon is much more common and significant in desperate patients who already have chronic pain — so they seek and tolerate intense therapy.

The experience of pain is affected by many factors, including emotional and psychological ones. People in chronic pain usually experience some degree of pain neurology dysfunction, and a breakdown of the relationship between how bad things feel and how much is really wrong. That breakdown can be seriously worsened by threatening sensations. Thus, people experiencing pain system dysfunction can have minor and major setbacks in response to excessively painful massage.

One of my readers suffered this kind of disaster. She was injured by “fascial release” therapy, a style which is often too intense and may focus on treating connective tissues to the exclusion of considering the patient’s comfort and nervous system.

I may have been too aggressive with a few patients over the years. I never did serious harm this way as far as I know, but I’m sure that I occasionally did more harm than good. This failure was due entirely to my ignorance of pain science: despite being an unusually well educated massage therapist, I simply did not know that an intense massage could change pain sensitivity itself. Does your therapist?

Poisoned by massage

People often feel sore and a bit “oogy” after strong massage, the phenomenon of post-massage soreness and malaise (PMSM). It’s routinely dismissed and rationalized by massage therapists as a necessary evil, a “healing crisis,” the effect of detoxification. That’s all bullshit. At best, it could just be a form of mild disorientation, basically feeling “weird” after an unusual and intense sensory experience. But it’s probably more biological, and actually the opposite of detoxification: a light poisoning.

Excessive pressure can probably cause rhabdomyolysis (“rhabdo”): poisoning by proteins liberated from injured muscle, known as a “muscle crush” injury. It would usually be mild with massage, but not necessarily.

For example: an 88-year old man collapsed the day after an unusually strong 2-hour session of massage therapy.10 He had too much myoglobin in his blood, and it was clogging his kidneys and generally making him feel rotten. It’s not a sure thing that his condition was cause by the massage — but it is quite likely. It is almost certainly a perfect example of one of those rare but serious complications of massage. Another case study comes up below.

True rhabdo is a medical emergency in which the kidneys are poisoned by myoglobin from muscle crush injuries. But many physical and metabolic stresses cause milder rhabdo-like states — even just intense exercise, and probably massage as well. There are many well-documented cases of exertional or “white collar” rhabdo, and there is a strong similarity between PMSM and ordinary exercise soreness. A rhabdo cocktail of waste metabolites and by-products of tissue damage is probably why we feel a bit cruddy after all biological stresses and traumas — including massage, sometimes.

PMSM is just an unavoidable mild side effect of strong massage. And for a few more vulnerable patients, it could actually be a little dangerous.

Impaired performance: the minor but educational example of pre-event sports massage

There’s a minor old idea in massage therapy that you can enhance athletic performance by stimulating or invigorating an athlete before they do their thing. It’s not nearly as popular an idea as post-event massage, but it’s still a thing.

Unfortunately, the evidence is fairly unambiguously negative. Three small studies since 2007 have all concluded that, at the best, precompetition massage is of no help to sprinters,1112 and one of them found that13 “massage decreased 60-meter sprint performance in comparison to the traditional warm-up.” It’s not clear if that means massage actually impaired performance or if it simply couldn’t match the well-established value of a warm-up … but athletes who choose pre-competition massage are still shooting themselves in the foot.

Pre-event massage is obviously potentially a problem for athletes because of all the other potential harms mentioned in this article. Even a hint of PMSM is clearly not what an athlete wants right before, say, a soccer match. But there a particularly likely problem with massage right before trying to be all sporty: massage can be discombobulating. A blast of novel stimuli can be surprisingly disorienting, even if it is also invigorating. And it doesn't take much to throw an athlete off-kilter.

It’s an interesting example of “harm,” because it would be trivial for anyone but a serious athlete. But if you’re really trying to excel, and every possible advantage matters, and the stakes are high — very high for some athletes! — then being even slightly off-kilter is actually a very serious side effect.

Getting on your nerves

Nerves aren’t nearly as vulnerable to pressure as people generally think — most of them can actually take quite a licking and keep on ticking without a single symptom — but they aren’t invulnerable. Push hard enough in the wrong place, and you can injure a nerve, of course. In a 2017 incident, a woman’s radial nerve was crushed by an aggressive massage in her upper, inner arm. It’s rare, but it happens.14

And I once caused such a nerve injury myself: it was a minor injury, but it did — augh — result in weeks of aggravating discomfort for my client.

The Archives of Physical Medicine & Rehabilitation reported a similar spinal accesory nerve injury: “a rare and illustrative case of spinal accesory neuropathy associated with deep tissue massage leading to scapular winging [the shoulder blade sticking out] and droopy shoulder as a result of weakness of the trapezius muscle.”15

The neck is a vulnerable spot

The neck is not an especially fragile structure, but it is in some people, and there’s always a danger — with any kind of neck manipulation — of disastrously messing with a critical vulnerability that’s lurking in the spine. This can lead to two main kinds of rare but truly dangerous side effects of massage: spinal cord injury associated with instability of the upper cervical spine, or stroke caused by tearing of the vertebral arteries. I’ve had personal experience with three cases:

  1. What happened to my barber — either a brain stem injury or mini-stroke caused by careless massage of a vulnerable neck.
  2. One of my own patients was injured the same way by another therapist. She vomited and retched for hours afterwards: the nasty effects of brain stem impingement, or ripping of an artery going to the brain.
  3. I came somewhat close to inflicting the same fate on another patient of mine early in my career, but I’m proud to say that I spotted the warning signs and avoided disaster.

These problems aren’t common, but that’s three in my own relatively short (10-year) career, so it’s hardly unheard of.16 And then there are examples I had no involvement in …

A weird case of brain artery damage (extracranial internal cartoid artery dissection, specifically) was reported in 2004 by the Southern Medical Journal: a 38-year-old woman gave herself a stroke by using a vibrating massage tool for long and too hard on her neck.17 Obviously such an incident has little to do with professional massage. Nevertheless, it demonstrates that the arteries of the neck are a little bit fragile — and I have no doubt that there are poorly trained or incompetent therapists out there would might get carelessly exuberant in this region, while trying to treat the scalenes: see Massage Therapy for Neck Pain, Chest Pain, Arm Pain, and Upper Back Pain.

More miscellaneous cases studies and tales of massage woe (some serious, some a bit silly)

A weird, extreme case study paper tells the horror story of one person’s awful experience with a severe reaction to (apparently) infrared heat and massage therapy.18 The trouble started after several treatments. His neck and arms were swollen, the pain became “unbearable,” and his “serum muscle enzymes were increased” — which means some degree of rhabdo, which implicates the massage itself as a significant mechanism of injury. Massage is not likely to blame for the incident, though — it was probably interacting with some unidentified vulnerability in the patient, such as a muscle disease or a complication caused by a medication. Clearly massage and heat alone do not normally cause such severe side effects! Nevertheless, the potential for awful interactions does exist, and this is a good example of it.

“Alternative therapies may have serious complications, and patients usually do not report them unless asked specifically,” the authors point out. Although notice that some of these are too serious not to report.

Headaches are an extremely unpredictable and complicated category of problems with countless possible causes, and they can be seriously aggravated by massage. I’ve heard many such stories over the years. One of the worst came from one of my own massage therapists, who suffered “the worst migraine of my life,” which started during a relatively innocuous neck and head massage. “I knew it was happening. I could feel it getting worse as she worked. I still can’t believe I didn’t stop the treatment.”

Stretching injuries. Stretch is sometimes applied to patients by massage therapists, sometimes very strongly, and of course they routinely recommend it. Although mostly safe, obviously you can overdo it. I know this one from personal experience: Stretching Injury.

Fractures. I am one-degree of separation from a patient whose femur (the big leg bone!) was fractured by a massage. It was a weak and vulnerable femur to a modest degree … but still, wow! It’s the only fracture I’ve ever heard of personally, but I bet there are a few other examples out there.

Intestinal rupture. In 2019, a 68-year-old man with chronic constipation had a habit of abdominal self-massage, and “did it hard” shortly before developing severe belly pain. He had ripped a five-centimetre hole in his upper colon, and bled a litre-and-half of blood into his abdomen before diagnosis. He got lucky, but this certainly could have killed him.19 While a severe injury may be exotically rare, consider how many people have suffered consequences less dire but still actually injured. How many one-centimetre tears have gone undiscovered? How many cases of “just” severe bruising?

Massage can dislodge blood clots, which can then get trapped in the lungs or brain or other tissues, a potentially deadly complication. This would likely only occur with vigorous and careless massage of higher risk patients, but there are a few published case reports,202122 and it’s probably an under-reported complication.

Falling off the table. An elderly and obese woman fell off a massage table while trying to turn over, “resulting in serious bodily injuries” …and a lawsuit, which is ridiculous.23 While I do not wish to make light of the woman’s injuries, I am including this case rather whimsically. It is a legitimate example of “what could possibly go wrong,” but it doesn’t have much more to do with massage than tripping on the doormat at a massage clinic. Still, massage tables are quite narrow…

Dizziness and vertigo attacks. These are classic non-specific symptoms that are easily triggered in many people, especially by massage for some reason,24 and just because many people are vulnerable to them for all kinds of reasons. There are potentially serious causes of dizziness/vertigo during a massage (see above), but there are probably many less worrisome cases as well. For instance, a reader told me this story:

I have Meniere’s disease. A month ago I had surgery: a surgeon cut my left ear “balance nerve” [vestibular nerve section] so it couldn’t send screwy signals to brain anymore. Post-surgery imbalance is expected for a few months as the brain adjusts, but a “vertigo attack” is supposed to be a thing of the past.

I went and had a two hour “deep tissue” massage. Near the end the room started to slowly rotate on me: the beginning of a vertigo attack! Do you think the massage could have caused this episode?

A good question without a good answer. Meniere’s is a peculiar disease, and the results of such a surgery are probably erratic and imperfect. I have no doubt a strong massage could trigger a vertigo attack in such a patient simply because practically anything can, including just stress, and a massage like that is a large dose of novel sensations and biological challenges (read: stress) — lots of potential triggers for Meniere’s, never mind in someone who got their vestibular nerve pruned just a month ago!

Lessons for professionals and patients

These are rare but real incidents. Healthy people are unlikely to be injured by massage. Most of dangers are related to undetected vulnerabilities, and they emphasize the importance of alternative health professionals being trained to spot the scary stuff. The measure of a health professional’s competence is not what they do with relatively healthy patients, but whether they have the training and humility to recognize more precarious clinical situations.

Massage therapists need to know that the most important part of their job is the smart management high-risk situations that they may see only a handful of times in their entire career. It’s like being on guard duty: 99.9% of the time, nothing bad happens. But how do you handle a curve ball when it finally comes? But they also need to know that chronic pain is a relative common dangerous situation, easily aggravated by

Consumers need to know that massage isn't perfectly safe, that a "no pain, no gain" attitude is the source of most of the danger, especially for chronic pain patients. They should run away from cocky therapists who trash-talk “mainstream” health care — they are the most likely to ignore, minimize, or rationalize side effects, while missing or misinterpreting serious symptoms.

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About Paul Ingraham

Headshot of Paul Ingraham, short hair, neat beard, suit jacket.

I am a science writer in Vancouver, Canada. I was a Registered Massage Therapist for a decade and the assistant editor of 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.

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.

What’s new in this article?

Six updates have been logged for this article since publication (2010). All updates are logged to show a long term commitment to quality, accuracy, and currency. more Like good footnotes, update logging sets apart from most other health websites and blogs. It’s fine print, but important fine print, in the same spirit of transparency as the editing history available for Wikipedia pages.

I log any change to articles that might be of interest to a keen reader. Complete update logging started in 2016. Prior to that, I only logged major updates for the most popular and controversial articles.

See the What’s New? page for updates to all recent site updates.

Jan 19, 2020 — Added a significant case study of severe injury to the colon from strong abdominal massage, and a story of a woman who was badly injured falling off her massage table. Also edited the intro to make it clear that the severe injuries we can read about are probably outnumbered by unreported/milder ones.

2018 — New section: “Impaired performance: the minor but educational example of pre-event sports massage.” Added and discussed “distraction from more appropriate care” to the introductory section. Updated the conclusion so it’s in sync with changes made in the last couple years.

2018 — Added article summary, and made numerous other miscellaneous improvements.

2018 — Added discussion of dizziness, vertigo, and Meniere’s disease.

2017 — Added emboli (blood clots stuck in vessels) with three case studies.

2016 — Minor reorganization of the article; added a couple more examples.

2010 — Publication.


  1. Cambron JA, Dexheimer J, Coe P, Swenson R. Side-effects of massage therapy: a cross-sectional study of 100 clients. J Altern Complement Med. 2007 Oct;13(8):793–6. PubMed #17983334 ❐
  2. Indeed, that seems very likely given the context. I doubt they would test painfully strong massage on 100 people without mentioning the intensity. However, painfully strong massage is quite common “in the wild.” Certainly intense massage is unusually common here in Vancouver, where there’s a regrettable professional predeliction for it.
  3. Ernst E. The Safety of Massage Therapy. Rheumatology. 2003;42 (9):1101–1106. PubMed #12777645 ❐ PainSci #54834 ❐

    Is massage safe? Researchers attempted to answer that question. Four databases were reviewed; all articles which reported adverse effects of any type of massage therapy were looked at. In the end, 20 reports were looked at. “The majority of adverse effects were associated with exotic types of manual massage or massage delivered by laymen, while massage therapists were rarely implicated.”

    The conclusion was that, while not entirely risk free, “serious adverse events are probably true rarities.”

  4. Posadzki P, Ernst E. The safety of massage therapy: an update of a systematic review. Focus on Alternative and Complementary Therapies. 2013;18(1):27–32. PainSci #53974 ❐


    OBJECTIVE: To update a systematic review evaluating the safety of massage therapy.

    METHODS: A literature search was carried out using four electronic databases for the period December 2001 to May 2012. All articles reporting adverse effects of massage therapy were retrieved. Adverse effects relating to atypical massage, aromatherapeutic massage oil or ice were excluded. No language restrictions were applied. Data were extracted and evaluated according to predefined criteria.

    RESULTS: Seventeen case reports and one case series were published since our previous review. The reported adverse effects comprised acute paraplegia and abdominal distension, bladder rupture, bilateral cerebellar infarction, cervical lymphocele, cervical cord injury, cervical internal carotid and vertebral dissection, chylothorax, haematuria, interosseous nerve palsy, myopathy, perinephric haemorrhage, rhabdomyolysis, severe headache, blurred vision, paraesthesia and focal motor seizures. In the majority of the reports, a cause–effect relationship was certain or almost certain. Serious adverse effects were most commonly associated with massage techniques applied to the neck area.

    CONCLUSION: Evidence suggests that massage may occasionally lead to moderately severe adverse effects.

  5. If someone spends $5,000 on massage therapy that has only a minor therapeutic effect, or none at all, is that an “injury”? It’s an insult, at the least!
  6. Ingraham. 💩 Massage Therapists Say: A compilation of more than 50 examples of the bizarre nonsense spoken by massage therapists with delusions of medical knowledge.  ❐ 8866 words.
  7. Many naturopaths, chiropractors, acupuncturists and massage therapists are overconfident of their diagnostic skills, and overlook or underestimate serious symptoms. This is one of the most basic and serious problems with the whole idea of having an “alternative” kind of medicine. For more information, see Missing Serious Symptoms: Alternative medicine often diagnoses overconfidently, overlooking or underestimating serious symptoms.
  8. Several dozen at least who experienced minor negative effects and a lighter wallet. I recall only about dozen or so having really poor experiences, mostly aggravated chronic pain. Only a handful of those were obviously significantly injured by massage. But those were sad cases.
  9. Woolf CJ. Central sensitization: Implications for the diagnosis and treatment of pain. Pain. 2010 Oct;152(2 Suppl):S2–15. PubMed #20961685 ❐ PainSci #54851 ❐

    Pain itself often modifies the way the central nervous system works, so that a patient actually becomes more sensitive and gets more pain with less provocation. That sensitization is called “central sensitization” because it involves changes in the central nervous system (CNS) in particular — the brain and the spinal cord. Victims are not only more sensitive to things that should hurt, but also to ordinary touch and pressure as well. Their pain also “echoes,” fading more slowly than in other people.

    For a much more detailed summary of this paper, see Sensitization in Chronic Pain.

  10. Lai MY, Yang SP, Chao Y, Lee PC, Lee SD. Fever with acute renal failure due to body massage-induced rhabdomyolysis. Journal of Nephrology, Dialysis and Transplantation. 2006 Jan;21(1):233–4. PubMed #16204282 ❐ PainSci #54301 ❐
  11. Goodwin JE, Glaister M, Howatson G, Lockey RA, McInnes G. Effect of pre-performance lower-limb massage on thirty-meter sprint running. J Strength Cond Res. 2007 Nov;21(4):1028–31. PubMed #18076229 ❐
  12. Fletcher IM. The effects of precompetition massage on the kinematic parameters of 20-m sprint performance. J Strength Cond Res. 2010 May;24(5):1179–83. PubMed #20386129 ❐
  13. Moran RN, Hauth JM, Rabena R. The effect of massage on acceleration and sprint performance in track \& field athletes. Complement Ther Clin Pract. 2018 Feb;30:1–5. PubMed #29389467 ❐
  14. Hsu PC, Chiu JW, Chou CL, Wang JC. Acute Radial Neuropathy at the Spiral Groove Following Massage: A Case Presentation. PM R. 2017 Apr. PubMed #28400223 ❐
  15. Aksoy IA, Schrader SL, Ali MS, Borovansky JA, Ross MA. Spinal accessory neuropathy associated with deep tissue massage: a case report. Arch Phys Med Rehabil. 2009 Nov;90(11):1969–72. PubMed #19887226 ❐
  16. For perspective, there are many real-but-rare scary things in medicine that rare enough that the huge majority of clinicians will never encounter them — not a single case in a full multi-decade career, as far as they know.
  17. Grant AC, Wang N. Carotid dissection associated with a handheld electric massager. South Med J. 2004 Dec;97(12):1262–3. PubMed #15646768 ❐
  18. Tanriover MD, Guven GS, Topeli A. An unusual complication: prolonged myopathy due to an alternative medical therapy with heat and massage. South Med J. 2009 Sep;102(9):966–8. PubMed #19668045 ❐
  19. Mori S, Ai T, Otomo Y. Laceration of the transverse mesocolon in an old man with a habit of abdominal massage for constipation: a case report. Surg Case Rep. 2020 Jan;6(1):1. PubMed #31898753 ❐ PainSci #52515 ❐

    The patient was misdiagnosed with a tumour at the hospital. A day later, still bleeding internally, a surgeon found the lesion and attempted to close it, but the tissue was too fragile for proper suturing. Luckily, the patient recovered surprisingly well, and his only complication was an ironic increase in constipation from a paralyzed intestine. When traumatized, the intestine stops contracting for safety.

    The authors of the report reasonably assume that the injury was caused by massage, but note other possible explanations, “such as rupture of small aneurysms.” However, the lesion was quite a bit too large to be explained by anything but the most obvious.

  20. Jabr FI. Massive pulmonary emboli after legs massage. Am J Phys Med Rehabil. 2007 Aug;86(8):691. PubMed #17667202 ❐ PainSci #53507 ❐

    A case report about a woman who suffered massive pulmonary emboli after extremely vigorous massage to her legs. The author speculates that it’s also possible to actually cause blood clots. “The incidence is very minimal, considering the popularity of massage therapy, but there is likely underreporting.” Short full text available as a (low-quality) PDF.

  21. Warren SE. Pulmonary embolus originating below knee. Lancet. 1978 Jul;2(8083):272–3. PubMed #79075 ❐

    Case report of an elderly woman who developed a lung embolus after her husband vigorously massaged her leg, which had a known deep vein thrombosis — a serious contraindication to massage which any competent massage therapist would certainly avoid. But not all of them, and not husbands as a general rule.

  22. Mikhail A, Reidy JF, Taylor PR, Scoble JE. Renal artery embolization after back massage in a patient with aortic occlusion. Nephrol Dial Transplant. 1997 Apr;12(4):797–8. PubMed #9141017 ❐

    A case report: “massage” in the form of walking on the back (not as rare or necessarily reckless as sounds) disloged a clot in a kidney article that had been grafted.

  23. I was contacted by the woman’s lawyer. “We feel there should have been some assistance to her turning over and that she was injured do to the lack of that assistance,” she wrote. But, unsurprisingly, she was “having difficulty finding cases or statutes to support her claim and would like to know if you have heard or experienced any situations as this in which to help guide me in the right direction.”

    My rather flummoxed reply:

    This seems to be firmly in the category of a "freak accident." Not only is falling off the table itself exceedingly rare (never heard of even that), but sustaining severe injuries is just insanely bad luck. A hundred people could fall off a massage table without getting anything more than bruise, maybe one fracture.

    This hazard didn't come up even as a hypothetical one single time in my training or in my 10-year clinical career. I don’t think is a clear duty of massage therapists to prevent people from falling off their massage tables… because it’s an impossible misfortune to predict and prevent, and the ability to do so is irrelevant to the training and skills of a massage therapist. In short, there is nothing anyone could do to reliably prevent such an incident.

  24. Nausea and fatigue, for instance, are also classic non-specific symptoms, but they seems like a much rarer side effect of massage. I have no idea why. The unusual positioning (face down) may have something to do with it.