Has a coach, trainer, or therapist “screened” you for injury risk and dysfunctional or performance-limiting movement patterns? The Functional Movement Screen (FMS) is a set of seven physical tests of coordination and strength, especially “core” strength, invented in 1997 and now in widespread use around the world. It was originally proposed as a trouble-detection system, which is baked into the name: it’s a “screen.”
Its use in the wild seems to over-reach this stated purpose.
FMS founder Lee Burton wrote in March, “The biggest critique we have gotten over the years is the lack of research to support use of the FMS” but “more and more research is becoming available relating to its scope and effectiveness.”1 I am not so sure that the evidence available to date is persuasive — the opposite, I fear — but meanwhile FMS is being promoted as though its powers are proven. Despite Burton’s statement, I think the marketing cart may be in front of the research horse — as so many carts are in the world of training and musculoskeletal health!
This isn’t a thorough review of FMS per se: it is focused on the abuse of FMS as a way to diagnose the average athlete or patient (or the closely related SFMA, which is actually advertised as a “movement based diagnostic system”). However, these concerns do cast doubt on the validity of FMS in general, as well as the much broader idea of corrective exercises, which need problems to correct, such as core weakness or “poor posture.” If FMS has problems, then probably so do simpler ideas about what needs fixing.
Functional Movement Screening in theory
“To date , there is no intervention study providing support for screening for injury risk.”
~ Bahr, 2016, British Journal of Sports Medicine2
A “screen” has a specific meaning in health care. It is not a diagnostic tool: it is just for detecting individuals who need diagnosis. This is a common concept in health care — think “mammogram” or “prostate exam”3 — but not so much in sport and rehabilitation. The complexities and ethics of screening are a bit exotic, normally debated in the context of vast public health initiatives.
Anoop Balachandran explains how screening is fundamentally a different ethical beast than diagnosis, because you are telling basically healthy people what might be wrong with them, and that raises the stakes4 (specifically the real risk of nocebo5):
… The validity of screens should be of the highest quality since you are “labeling” people and hence we should have very solid proof that people will be better off in the long run. When someone scores less than the cut off in the FMS, you tell them their chance of getting injured is extremely high. This is a great way to get someone to move less or have fear of movement or spend his or her time and money trying to fix it with their trainer.
Anoop Balachandran, MSc Exercise Physiology, MSc Human Performance
Nevertheless, it was a fine idea to try to introduce FMS into the world of performance and rehab. It would have been a good idea even if that was not the actual original intent. Truly, we could use a good screen. It’s just not clear that FMS is actually being used that way. Indeed, it’s seems clear that it’s not.
Functional Movement Screening in practice: a diagnostic tool?
The FMS is officially not meant for assessing people who are already hurting or injured, just “limitations” and risk factors for injury. And yet the people that gave us FMS also teach a closely-related but much less well-known “movement based diagnostic system,” the SFMA. Whatever it’s called, professional are definitely diagnosing based on movement, one way or another — either abusing the concept of FMS, or using SFMA as intended.
So either FMS should change its name, or it should actually only be used as a screen — only to establish that “something is wrong here” or “something is still wrong here” — and not to figure out what is actually wrong. But in the real world, FMS is often promoted as a tool that can “detect” biomechanical problems and therefore justify training or treatment methods to “correct” them. Again, founder Lee Burton: “FMS is designed to identify movement pattern dysfunctions, thereby helping create the best possible intervention.”6
That’s no screen — that’s diagnosis!
And the “best possible intervention” is often expensive, of course. Athletes and sports teams may invest heavily in following advice that is based substantially on FMS assessments.
FMS certification and exaggeration of its benefits is also often used to create an impression of diagnostic competency in professionals — coaches and trainers — who are trying to seem more like therapists and should not be diagnosing at all (or even seem to be). Athletes and fitness buffs are often “enablers” in this regard.7
This is a general problem with the industry, of course, but FMS certification is a prominent example.
A little searching on the internet can quickly scare up examples of FMS being used diagnostically. In just a few seconds, I found a chiropractic website with the claim that FMS “uncovers limitations and asymmetries in the movements of healthy individuals.” It goes on “Corrective exercises can then be prescribed to overcome these deficiencies.”8 The overconfident use of FMS to justify specific treatment is blatant here.
Or look at this amusing example of overconfident promotion of FMS: big diagnostic and treatment promises, to the tune of cheesy 80s rock anthem “Eye of the Tiger.” (Admittedly, it’s a nostalgic classic. My foot taps … ) In the video, modestly titled FMS: Get Your Best Body, a chiropractor demonstrates FMS and explains:9
Depending on your score and asymmetrical results from left to right side I can determine your non-painful dysfunction. We correct that and you become a better athlete. Stronger, more flexible, stable, mobile and powerful. Oh, and you can get out of chronic pain…
Are these just isolated cases of FMS hype? Perhaps FMS training and certification would minimize such overstatement? Perhaps. There may well be FMS practitioners who overstate the claims of FMS, going beyond its intended use. But FMS certification is granted by a company that promotes it with language surprisingly similar to the examples above. The official FMS website is generally heavy with promotional language and light on the science:10
… the FMS readily identifies functional limitations and asymmetries … used to target problems … directly linked to the most beneficial corrective exercises to restore mechanically sound movement patterns … identify those exercises that will be most effective to restore proper movement …
“About” page of FunctionalMovement.com11
Visit the FunctionalMovement.com, have a look around, and judge for yourself. Does it seem like they are promoting a screening tool with modest goals and appropriately limited scope? Or a diagnostic tool “directly linked” to treatment?
The Functional Movement Screen fails to detect recent injury
The use of FMS as a screen and a diagnostic tool has been particularly problematic because “normal” test results had never been defined. A low FMS score supposedly means that you are more likely to get hurt, but … lower than what? FMS needs a baseline — or even several of them, for a variety of well-defined populations.
A 2011 study in International Journal of Sports Physical Therapy set out to get the numbers for normal.12 According to Schneiders et al the idea that FMS has diagnostic power is (emphasis mine):
… based on the assumption that identifiable biomechanical deficits in fundamental movement patterns have the potential to limit performance and render the athlete susceptible to injury.
However, their experiment could not even detect a difference in test results in people who had actually been injured recently. The results
demonstrated no significant differences on the composite score between individuals who had an injury during the 6 last months and for those who had not.
Past injury is probably a risk factor for future injuries — for instance, the reasons for the original injury may persist and cause re-injury, or a new injury. If FMS cannot detect any sign of recent injuries, it seems unlikely that it can detect the risk of future injuries, let alone be used as a basis for a specific therapy.
This is not surprising. In general, rehab science has generally been failing for decades to nail down correlations between even the most obvious-seeming “biomechanical bogeymen” and common injuries, let alone the smoking gun of a true cause. Even if there are biomechanical causes of pain and injury — and doubtless there are a some — I wouldn’t expect a set of physical tests to reveal them in an exact or reliable way.
Anoop Balachandran criticizes the rationale for FMS in more detail:13
Why should mechanical stress causes by “faulty movement patterns” always “lead to microtrauma and injury”? Why can’t tissues just positively adapt and get stronger just like a normal biological tissue? If indeed faulty movement patterns were the cause of injury, all those cerebral palsy patients, stroke victims, people with neurological disorders and amputees should be in complete pain. There are double amputees who run faster than most of us and still feel no pain. The compensations and asymmetries are 100% in these amputees and they should be crying out loud in pain than running around. Maybe that movement pattern is “ideal” for them and the tissues have adapted to it.
Anoop Balachandran, MSc Exercise Physiology, MSc Human Performance
A long, fragile chain of reasoning
FMS is classic example of structuralism — the excessive preoccupation with biomechanical factors in injury and pain.16 In particular, it depends on the faddish notion that “core strength” is important, an idea that has been harshly criticized by experts17 and has generally failed to live up to its reputation.18 At best, the value of core strength remains controversial. At worst, it’s been a serious red herring in the fitness and therapy industry.
Structuralism typically depends on complex chains of reasoning that are only as strong as their weakest links. For FMS to deliver what it promises, all the of the following links must be sound:
- Non-obvious functional limitations must be consistent signs of “dysfunction.” If they are …
- Subtle dysfunction must in turn actually be a cause of injury and limited athletic performance. This theoretetical foundation highly controversial and complex. But even if it’s solid … which is a huge if …
- FMS practitioners must be able to reliably detect the existence of specific non-obvious functional limitations. schneiders11 et al. found that this link is okay. If it really is …
- FMS practitioners must be able to reliably associate those functional limitations with a much more complex array of potential problems that could be causing them. Here again we see the problem with the difference between screening and diagnosing. Perhaps anyone can be trained to spot poor performance on FMS tests. But can anyone identify the cause of that poor performance? What if it’s an early sign of a slow-developing neurological disease? Diagnosis is a vastly more complex beast than screening. If FMS practitioners can diagnose reliably …
- The identified dysfunctions must actually be correctable in principle. A basic problem with many biomechanical theories of pain is that, even if true, there’s nothing that can be done about them. If they are correctable …
- The FMS practitioners must then be able to reliably prescribe appropriate correction.
If FMS practitioners can do all that — and do it reliably — then they can deliver what they are promising.
2017 update: Is the FMS science here yet?
It’s trickling in. There’s probably enough for some tentative conclusions now.
The first version of this article was written in 2011, mostly hype-griping, and it went untouched for three years while FMS promoters carried on making claims about a “growing body of research,” of course. The research wasn’t persuasive before, and maybe things have gotten worse since.
A summer 2014 paper by Whiteside et al echoes all my original concerns, but with harder data.19 The researchers focused on the accuracy of FMS grading in particular: “virtually no investigations have probed the accuracy of FMS grades assigned by a manual tester.” So they probed it! They compared “the FMS scores assigned by a certified FMS tester to those measured by an objective inertial-based motion capture system.” Alas for FMS, the results were “poor,” which is exactly what I’ve been betting on all along.>
Manual grading may not provide a valid measurement instrument. The levels of agreement between the two grading methods were poor in all six FMS exercises. It appears that manual grading of the FMS is confounded by vague grading criteria.
The discussion section of the article is detailed, readable, and full of ominous understatement. “Dubious grading presents a concern for FMS clientele,” they write. They graciously allow that, with better objective criteria, FMS grading might “improve to acceptable levels.” Meanwhile, FMS testers are officially encouraged to aim for lower scores when in doubt, but in this test, even under scrutiny, apparently they didn’t have much self-doubt, consistently scoring “0.54 points higher than the IMU system.” (I’m shocked, simply shocked, to learn that FMS practitioners might be a tad overconfident!) The authors also point out that FMS has not only failed to reliably forecast injuries, but all FMS predictions may be “a product of specious grading.” Which is hardly surprising, since FMS fails to take into account “several factors that contribute to musculoskeletal injury.” These concerns must be addressed “before the FMS can be considered a reliable injury screening tool.”
Clearly more research is needed — of course! Naturally! But it’s worse than that:
The high potential for subjective and/or inaccurate grading implies that standard procedures must be developed before FMS performance and injury rates can be conclusively studied.
Before it can be studied. They seem to be saying that not only is the cart is still in front of the FMS horse, the horse may now be falling well behind. FMS research so far may be a bit of a write-off, because it can’t inform us without better criteria, and everyone should probably just go back to the drawing board and try again. Which suggests that this article is still reasonably sound after three years without an update.
Despite these limitations, a wave of research produced enough data to be worth of review by 2015.
The first research review
The first review of the predictive validity of FMS was published in late 2015, with a predictably and resoundingly negative conclusion based on generally mediocre data from seven studies:20
Based on analysis of the current literature, findings do not support the predictive validity of the FMS. Methodological and statistical limitations identified threaten the ability of the research to determine the predictive validity of FMS.
And another not-positive review
A 2016 review in the British Journal of Sports Medicine surveyed 17 “mostly low quality” studies of the relationship between leg injuries and movement quality, concluding it is “inconsistent.”21 In other words, we still have no idea if we can tell who’s going to get leghurt based on screening people for quality-of-movement trouble. Standard caveats about garbage-in-garbage-out reviews seem to apply here: the results are officially inconclusive, but the absence of a clear positive signal is damning.
Since that review, a good quality study in British Journal of Sports Medicine has reinforced all the negative results:22 screening results of a few hundred soccer players were not associated with lower limb injury, and could not even distinguish between injured and uninjured players. As one of the authors put it, “Any way we sliced it, Functional Movement Screening was no help in predicting injured football players.”
Not so positive after all
A 2017 study loudly, over-confidently declared in its title that “scapular dyskinesis [“bad” shoulder movement] increases the risk of future shoulder pain by 43% in asymptomatic athletes.”23 This seems to defy skepticism about the importance of scapular dyskinesia — and therefore the value of screening for it. And it was cited that way by FMS proponents.
But the headline is extremely misleading. This is a great example of lying with statistics: it’s only a 43% greater relative risk, relative to a small total count of injuries. The difference in absolute risk is very minor, and the authors concede in the body of the paper that “screening for scapular dyskinesia is not a useful approach to predict shoulder pain.” Many shoulder problems almost certainly are not announced by subtle scapular movement issues. For instance, frozen shoulder is a strange but common condition with metabolic roots, and probably there isn’t the slightest reliable clue that it’s coming before it does.
A caution is not a dismissal: I cannot conclude that FMS has no value, although the evidence is sure leaning that way. All I can do here is raise a concern that the FMS is being applied inappropriately by many trainers, and seems to be resting on a number of questionable and untested assumptions. The burden of proof is (still) on FMS proponents to substantiate their claims, and the evidence so far mostly shows that they have barely really gotten started on that. Please take it with a grain of salt if anyone tries to tell you what’s wrong with you based on FMS testing.
I’ll give the last word to Tumminello, Silvernail, and Cormack, from their excellent article on this topic in Personal Training Quarterly:24
It is often assumed that identified so-called “dysfunctions” in posture, movement quality, or body function are reliably predictive of potential injury and performance, the preponderance of the scientific evidence casts a great amount of doubt on any claims about the strength and reliability of such relationships. This is because natural variations in human posture, movement and mobility/flexibility make identifying strict ideas of what is “correct” difficult and possibly invalid in many cases. Humans naturally move in different ways to accomplish different tasks, and identifying small variations in that movement as a “dysfunction” may not be very useful or helpful.
Worse yet, it could be harmful:
patients/clients with beliefs about their body that center on fragility/risk of harm, the importance of appropriate posture, or the need to move in specific ways to avoid injury are more likely to have pain and less likely to recover from a future problem.25 That is the opposite of the kind of physical and psychological resiliency that personal training is designed to build.
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About Paul Ingraham
I am a science writer, former massage therapist, and I was the assistant editor at ScienceBasedMedicine.org for several years. I have had my share of injuries and pain challenges as a runner and ultimate player. My wife and I live in downtown Vancouver, Canada. See my full bio and qualifications, or my blog, Writerly. You might run into me on Facebook or Twitter.
Special thanks to Scot Morrison, CSCS, student DPT; and Jason Silvernail, DPT, DSc, FAAOMPT, for their assistance in preparing this article. Thanks also to other members of SomaSimple.com, who also had many useful suggestions.
What’s new in this article?
Six updates have been logged for this article since publication (2011). All PainScience.com updates are logged to show a long term commitment to quality, accuracy, and currency. more
Like good footnotes, update logging sets PainScience.com 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.
2017 — Science update: cited Hickey et al, a paper about shoulder dyskinesia with a unusually misleading title.
2017 — Added a couple quotes, citations to two new reviews, and some clarifications about the role of SFMA versus FMS.
2017 — Science update based on the first systematic review of studies of the predictive validity of FMS.
2015 — Minor science update.
2015 — Added new section, based on Whiteside. A little miscellaneous modernizing and editing.
2011 — Added numerous footnotes. Added a new section, “A long, fragile chain of reasoning.”
2011 — Publication.
- Burton, Lee. Research Statement and Review. functionalmovement.com Mar 7, 2011.
BACK TO TEXT
- Bahr R. Why screening tests to predict injury do not work-and probably never will … : a critical review. Br J Sports Med. 2016 Jul;50(13):776–80. PubMed #27095747. ❐ BACK TO TEXT
- Both of these well-known and little-loved procedures are used to flag individual who need further assessment. In no way can a mammogram or prostate exam actually diagnose. The distinction is clear in these cases. (Note: in Canada, we have screening mammograms; in other countries, they are used used diagnostically. So perhaps it isn’t the best example for an international audience. But is also just another way of emphasizing the difference between screening and diagnosing.) BACK TO TEXT
- Balachandran, Anoop. Functional Movement Screen: Is it Really a Screen? exercisebiology.com, January 21, 2011.
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- “Nocebo” is Latin for “I shall harm” (which I think would make a great supervillain slogan). It refers to the harmful effect of … nothing but the belief in or fear of a harmful effect. Give someone a sugar pill and then convince them you actually just fed them a deadly poison, and you will probably witness a robust nocebo effect. A common funny-if-it’s-not-you nocebo in general medicine is the terror of “beets in the toilet”: people eat beets, and then think there’s blood in the toilet, and call 911. Nocebo is a real thing, and not to be messed with. It is one of the chief hazards of excessive X-raying and MRI scans, for instance: showing people hard evidence of problems that often aren’t actually a problem. A screening test that reveals alleged problems might do it too. BACK TO TEXT
- Burton, Mar 2011, Op. Cit.
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- It’s truly amazing how much credit amateurs will give to medically unqualified and barely-regulated professionals like trainers, fitness instructors, and coaches. It can be difficult for a personal trainer, for instance, to resist the temptation to answer a question as if they have the knowledge that a client wants to give them credit for. My mother is a fitness instructor, and routinely amuses me with tales of the questions that class participants will ask her in all earnestness: real medical questions! Admirably, she refuses to even speculate, and decivisely refers them to actual health care professionals — which is exactly what a fitness instructor should do. BACK TO TEXT
- Functional Movement Screen. chiropractorincincinnati.net. No publication date. Accessed 7/11/11.
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- “Dr. Perry.” Functional Movement Screen: Get Your Best Body. YouTube.com, April 4, 2009, accessed 7/13/11.
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- FMS Research Articles functionalmovement.com, no publication date, accessed 7/09/11. This page lists four items. One is a blog post reviewing research, but not reporting on new research.
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- What is FMS? functionalmovement.com, no publication date, accessed 7/09/11.
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- Schneiders AG, Davidsson A, Hörman E, Sullivan SJ. Functional movement screen normative values in a young, active population. Int J Sports Phys Ther. 2011 Jun;6(2):75–82. PubMed #21713227. ❐ PainSci #55282. ❐ BACK TO TEXT
- Balachandran, Anoop. Functional Movement Screen. exercisebiology.com, November 29, 2008.
BACK TO TEXT
- Tumminello N, Silvernail J, Cormack B. The Corrective Exercise Trap. Personal Training Quarterly. 2017 Mar;4(1). PainSci #52905. ❐ BACK TO TEXT
- Parchmann CJ, McBride JM. Relationship between functional movement screen and athletic performance. J Strength Cond Res. 2011 Dec;25(12):3378–84. PubMed #21964425. ❐
This experiment compared direct measures of athletic performance like sprinting speed and vertical jump with less direct measures like maximal squat strength (the most they could lift in one squat) and even less direct measure like scores on the functional movement screen (FMS). In theory, FMS testing can predict athletic performance. In practice, in this test, it did not “relate to any aspect of athletic performance.” But squat strength did!BACK TO TEXT
- PS Ingraham. Your Back Is Not Out of Alignment: Debunking the obsession with alignment, posture, and other biomechanical bogeymen as major causes of pain. ❐ PainScience.com. 19947 words. BACK TO TEXT
- Lederman E. The Myth of Core Stability. J Bodyw Mov Ther. 2010 Jan;14(1):84–98. PubMed #20006294. ❐ PainSci #55669. ❐ BACK TO TEXT
- Unsgaard-Tøndel M, Fladmark AM, Salvesen O, Vasseljen O. Motor Control Exercises, Sling Exercises, and General Exercises for Patients With Chronic Low Back Pain: A Randomized Controlled Trial With 1-Year Follow-up. Phys Ther. 2010 Jul. PubMed #20671099. ❐
This study tested two popular exercise options for chronic low back pain — core coordination, core strengthening — and compared them to a neutral third type, general exercise. Over a hundred participants worked with “experienced physical therapists” once a week for eight weeks. This is a particularly good test, because it is a good approximation of what a motivated patient might do: paying for eight weekly sessions of training is a greater and more disciplined effort than many people make, and yet still reasonably affordable and achievable.
Pain and disability were measured before and after, and at a one year follow-up. Unfortunately, there were no differences: “This study gave no evidence that 8 treatments with individually instructed motor control exercises or sling exercises were superior to general exercises for chronic low back pain.”
Perhaps more training would have yielded better results, but it’s hard to imagine that it would be worth the additional expense and effort for what would surely be a minor difference. And perhaps a different exercise therapy would have performed better, but the ones tested here are exactly the kind of thing that is almost always recommended to patients — so if there’s a better kind of exercise therapy, it’s certainly unknown and unproven.BACK TO TEXT
- Whiteside D, Deneweth JM, Pohorence MA, et al. Grading the Functional Movement Screen™: A Comparison of Manual (Real-Time) and Objective Methods. J Strength Cond Res. 2014 Aug. PubMed #25162646. ❐ BACK TO TEXT
- Dorrel BS, Long T, Shaffer S, Myer GD. Evaluation of the Functional Movement Screen as an Injury Prediction Tool Among Active Adult Populations: A Systematic Review and Meta-analysis. Sports Health. 2015;7(6):532–7. PubMed #26502447. ❐ PainSci #53719. ❐ Dorrel et al. found seven studies to review: one of them they rated fair, two mediocre, four poor. Garbage in garbage out? Maybe — but enough to get a strong sense that there’s not much here to find. BACK TO TEXT
- Whittaker JL, Booysen N, de la Motte S, et al. Predicting sport and occupational lower extremity injury risk through movement quality screening: a systematic review. Br J Sports Med. 2016 Dec. PubMed #27935483. ❐ BACK TO TEXT
- Bakken A, Targett S, Bere T, et al. The functional movement test 9+ is a poor screening test for lower extremity injuries in professional male football players: a 2-year prospective cohort study. Br J Sports Med. 2017 May. PubMed #28512188. ❐ BACK TO TEXT
- Hickey D, Solvig V, Cavalheri V, Harrold M, Mckenna L. Scapular dyskinesis increases the risk of future shoulder pain by 43% in asymptomatic athletes: a systematic review and meta-analysis. Br J Sports Med. 2017 Jul. PubMed #28735288. ❐ BACK TO TEXT
- Tumminello 2017, op. cit. BACK TO TEXT
- Darlow B, Dean S, Perry M, et al. Easy to Harm, Hard to Heal: Patient Views About the Back. Spine (Phila Pa 1976). 2015 Jun;40(11):842–50. PubMed #25811262. ❐ BACK TO TEXT