Why do you pay your physical therapist the big bucks? So you can learn about things like deep cervical flexor (DCF) training! This is a trendy, “technical” innovation in rehab for neck pain patients, but I fear it mostly just makes therapists sound like they know more than they do.
Exercise in general, and strengthening especially, is probably good for chronic neck pain (and many other kinds of pain). But this kind of fiddly, “advanced,” and “specific” training has a lot of problems, and DCF is a particularly strong example of “The Corrective Exercise Trap” in the world of rehab.1
This is a conceptual twin of training for “core” strength for low back pain, by the way. It also has a lot in common with the absurd mystique of the psoas muscle.2
Can you meaningfully exercise these deep neck muscles, more than the superficial ones? Would it matter if you could?
The core idea: why would we need to train the deep cervical flexors?
Some neck pain patients may have impaired DCF muscle motor control and strength,3 and use their superficial neck flexors instead4… plausible, and interesting if true, but the data isn’t exactly a slam dunk.
DCF dysfunction, if it is a real phenomenon, obviously could just be a symptom of neck pain, and not a cause. It’s completely plausible that pain is a source of inhibition of the deep cervical flexors. The only way to settle it one way or the other is with a certain kind of long-term study that no one has ever done.
But no one’s actually waiting for that, of course.
If at first you don’t know, assume!
While we’re waiting for the right science — and it’s going to be a long wait — many clinicians have predictably assumed “cause.” If you run with the assumption that DCF dysfunction does actually cause neck pain, then obviously that means DCF training might help. It’s a predictable assumption because it gives therapists something to therapize, and they can always be counted on to jump on these opportunities.
These assumers have been encouraged by a few scraps of research showing that DCF training improves DCF function,5 which isn’t really surprising. News flash: muscles adapt to exercise! You heard it here first.
But even that is being generous. When I say those three studies are “very weak” — the clinical trials of DCF training as a treatment for neck pain — I mean maybe “total garbage”: all three are in suspected predatory journals (pay-to-publish journals with no real peer review).9 If so, they have no value (and, if so, their existence just raises serious questions about the ethics, credibility, and biases of the researchers who are keen on DCF training).
But even taken at face value, the data they present isn’t compelling. And even if it were more impressive, it would need replication from sources of less uncertain quality.
A profusion of low quality science is a major problem in modern healthcare, especially physical therapy, and 13 Kinds of Bogus Citations are used to prop up all kinds of quackery and pseudo-quackery.
How to train your deep cervical flexors … if you must
As with any form of exercise, why not try? Time spent getting any kind of stronger is never entirely wasted. So how do you train your DCFs?
Basically you just tilt and tuck your chin repeatedly. (“Advanced” exercise!) Ideally you’d do that upside down, so that you’re lifting the weight of your head while you do it, but it’s not very practical. Next best thing is lying down …
- Lie down face up on a firm surface.
- Tuck your chin in (tilt and retract). Open your mouth fairly wide as well (inhibits the sternocleidomastoid a bit10).
- Lift your head ever-so-slightly and hold for a few seconds.
Repeat until annoyed by this finicky business. And don’t worry, we’re laughing with you, not at you.
So what does work, smartypants?
I’m being flippant, obviously, but it reflects my serious professional opinion: DCF training is nonsense and belongs in the physical therapy hall of shame. There’s no way in hell there’s a specific therapeutic effect here. It’s classic structuralism (excessive focus on biomechanics) and “amusing the patient while nature cures the disease.”
About Paul Ingraham
I am a science writer in Vancouver, Canada. I was a Registered Massage Therapist for a decade and the assistant editor of ScienceBasedMedicine.org for several years. I’ve had many injuries as a runner and ultimate player, and I’ve been a chronic pain patient myself since 2015. Full bio. See you on Facebook or Twitter., or subscribe:
This article is an abridged excerpt from my book-length neck pain tutorial. This version is about 1,200 words, and the full chapter in the book is about double that. It is generally more detailed, addresses the significance of coordination as well as strength and endurance, and adds some more points about actually doing DCF training. The neck pain book has a substantial free introduction, and it’s twenty bucks to unlock the remainder:
- The Complete Guide to Neck Pain & Cricks — An extremely detailed guide to chronic neck pain and the disturbing sensation of a “crick”
And some other (completely free) related reading around PainScience.com:
- The Complete Guide to Chronic Tension Headaches — A detailed, science-based tour of stubborn headache diagnosis and treatment, for both patients and professionals
- Can Massage Therapy Cause Nerve Damage? — It is possible, but hard to do, rare, and the damage is usually minor
- Spinal Subluxation — Can your spine be out of alignment? Chiropractic’s big idea has been misleading patients for more than a century
- A Recipe for Chronic Neck Pain After Whiplash — Researchers discover some surprising risk factors for chronic neck pain in the aftermath of whiplash
What’s new in this article?
Jun 10, 2023 — Minor polish and integration with other PainSci content.
2018 — A minor but fun addition about the DCFs being the “psoas of the neck.”
2018 — Publication.
- Tumminello N, Silvernail J, Cormack B. The Corrective Exercise Trap. Personal Training Quarterly. 2017 Mar;4(1). PainSci Bibliography 52905 ❐
Tumminello, Silvernail, and Cormack decisively but gently and diplomatically tip over this most sacred cow of personal training and therapy: corrective exercise, which is based on the idea that there is something in-correct about patients — fragile, weak, or uneven — which can be both identified and fixed by specific, expertly prescribed exercises, mainly strengthening and stretching exercises, the staples of stereotypical physical therapy. The trap is the belief that this “technical” approach is inherently superior to good exercise in general.
The danger here is that many fitness professionals might end up making their training process more about a formalized evaluation procedure and less about good personal training. …In order to spot a physical flaw that needs to be corrected, one must begin by having a reliable measure of whether or not it is actually problematic in the first place.
Spoiler alert: there is no such reliable measure! Corrective exercise is built on wishful thinking. Screening for movement dysfunctions has been failing one fair scientific test after another. The importance of posture has been wildly exaggerated. The importance of anatomical variation has been virtually ignored.
These authors all have excellent credentials and top notch clinical reasoning skills. These are smart guys tackling several thorny sub-topics like postural dysfunction, movement dysfunction, core stability, and — most important of all, I think — the “nocebo concerns” with corrective exercise: “when clients are told such things about themselves from an authority figure (as they might be during some corrective exercise evaluations), that this potentially makes one’s clients less resilient and more prone to injury and pain.”
Translation sans diplomacy: stop #%&^ telling patients they are fragile and weak!
- The iliopsoas, or just “psoas,” is a big hip flexor on the front of the lower spine that is virtually worshipped by a certain kind of massage therapist. Allegedly it has great clinical significance. These folks also get excited about the deep cervical flexors, especially the longus colli muscle, “the psoas of the neck.” It’s not a flattering association for DCF training: psoas hype is silly. See Psoas, So What? Massage therapy for the psoas major and iliacus (iliopsoas) muscles is not that big a deal.
- Falla DL, Jull GA, Hodges PW. Patients with neck pain demonstrate reduced electromyographic activity of the deep cervical flexor muscles during performance of the craniocervical flexion test. Spine (Phila Pa 1976). 2004 Oct;29(19):2108–14. PubMed 15454700 ❐
- Jull G, Falla D. Does increased superficial neck flexor activity in the craniocervical flexion test reflect reduced deep flexor activity in people with neck pain? Man Ther. 2016 Sep;25:43–7. PubMed 27422596 ❐
- Jull GA, Falla D, Vicenzino B, Hodges PW. The effect of therapeutic exercise on activation of the deep cervical flexor muscles in people with chronic neck pain. Man Ther. 2009 Dec;14(6):696–701. PubMed 19632880 ❐
A small, flawed study with very little power to demonstrate anything important. The author is probably a “true believer” in deep neck flexor training, as the progenitor of exercise protocols to achieve that. It is not a study of the effect of training the deep neck flexors on neck pain, but simple a study of the effect of training on muscle activation. The efficacy of this for neck pain is assumed, and so the study reads a lot like a small “fishing expedition” looking for evidence to explain a benefit that hasn’t actually been demonstrated by any other research. This paper strikes me as typical of the poor quality of this journal.
- Kim JY, Kwag KI. Clinical effects of deep cervical flexor muscle activation in patients with chronic neck pain. J Phys Ther Sci. 2016 Jan;28(1):269–73. PubMed 26957772 ❐ PainSci Bibliography 53187 ❐
- Iqbal ZA, Rajan R, Khan SA, Alghadir AH. Effect of deep cervical flexor muscles training using pressure biofeedback on pain and disability of school teachers with neck pain. J Phys Ther Sci. 2013 Jun;25(6):657–61. PubMed 24259822 ❐ PainSci Bibliography 53185 ❐
- Gupta BD, Aggarwal S, Gupta B, Gupta M, Gupta N. Effect of Deep Cervical Flexor Training vs. Conventional Isometric Training on Forward Head Posture, Pain, Neck Disability Index In Dentists Suffering from Chronic Neck Pain. J Clin Diagn Res. 2013 Oct;7(10):2261–4. PubMed 24298492 ❐ PainSci Bibliography 53184 ❐
- A “predatory journal” is a fraudulent journal that publishes anything for pay (literally anything, even gibberish), without peer review. This is a new kind of junk science, as bad as any pseudoscience. These “journals” are scams: their purpose is to rip off academics who are desperate to “publish or perish.” There are thousands of predatory journals now, many of which have high superficial legitimacy (they look a lot like real journals, e.g. actually indexed in PubMed). Some of the research is undoubtedly earnest, but cannot be trusted without peer-review. See Gasparyan et al and 13 Kinds of Bogus Citations.
- Park J, Ko DH, Her J, Woo J. What is a more effective method of cranio-cervical flexion exercises? J Back Musculoskelet Rehabil. 2018;31(3):415–423. PubMed 29332030 ❐