Brace yourselves, we’re talking Core Stability with Ben Smith

What exactly is 'core stability'? Well it means many different things to different people, but within the world of physiotherapy the term has come to symbolise a series of exercises that asks you to brace and pull in your deep abdominal muscles as you perform different movements. These are commonly prescribed by many physios to those with longstanding back pain, but, do they help, do they make a difference, and what's the evidence for using them?

To try and answer these questions I'm delighted to welcome Ben Smith to 'The Sports Physio'. Ben is an MSK Physiotherapist working in the NHS in Derby. He’s currently completing a Masters at Nottingham University and is working towards a PhD application in relation to PFJS. His specialist interest is integrating evidence into practice, particularly with spines and knees, and can be followed on Twitter @benedsmith Ben has very kindly written an extremely well researched and evidenced based piece looking at the use of core stability exercises for chronic low back pain.

Now before we get started, this is a subject I've touched on before in my rants and ravings online and those who know me will already know my own strong, cynical and sceptical views on this subject, that being I have very little time or patience with core stability exercises within physiotherapy and that I find the practice of asking those with back pain to brace and clench things tight and rigid, absurd and complete nonsense, so to avoid the screams, accusations and shouts of bias and unfairness I will extend an invitation to anyone willing or wanting to defend the role of core stability exercises the chance to write a reply article in response to Ben's, just leave a comment below with your request and I will be in touch!

So without further ado lets get into it and I'll hand over to Ben as we delve into the role of 'Core stability and chronic low back pain'

Introduction

Physiotherapy treatments for LBP range from spinal manipulations, mobilisation, advice, general exercises and specifically tailored exercises (Liddle et al., 2009). Despite doubts raised about its effectiveness compared with other forms of treatment (May et al., 2008), the most frequently given exercise by physiotherapists is core stability (Liddle et al., 2009). The exercise has become the unquestioned treatment of choice for physiotherapist.

This blog will examine relevant evidence surrounding the effectiveness and the underpinning physiological effects of core stability exercises for chronic LBP.

Background

It has been suggested that in normal people the muscle transversus abdominis (TrA) activates prior to limb movement in an anticipatory feed forward mechanism, and further suggested that this activation is delayed in patients with chronic LBP (Hodges et al., 1996, 1999; Richardson et al., 1999). It was therefore hypothesised that addressing this delayed feed forward mechanism through therapeutic exercise would have a positive effect on patients with chronic lower back pain, furthermore that people without current symptoms, but a history of symptoms, would be at a reduced risk of re-injury by following this treatment protocol (Hodges et al., 1999). An exercise regime aimed at isolating TrA was then developed, designed to retrain motor skills and ‘reset’ the delayed feed forward mechanisms (Richardson et al., 1999).

Underpinning physiological effects

The hypothesis that TrA training can have a positive impact on patients with chronic LBP is based upon two premises. Firstly, that TrA is the key component to spinal stability, and secondly that training can ‘reset’ the delayed timing issue.

The first premise, that TrA is the key component to spinal stability, is a huge assumption, and a theory that fails when tested. It centres upon the biomedical model of causation, as described by Bradford Hill (1965). It is a model of causation whereby biological changes are used to describe states of illness. It makes assumptions based upon the considered ‘normal’ state in which a body should be (Tyreman, 2006), with any variations from this ‘normal’ state being considered abnormal, and ultimately leading to illness. What we know is that this model is extremely simplistic, and fails to take into account psychological and social factors (Tyreman, 2006).

More recent studies have shown that the onset timing of TrA does not have an ideal pattern in pain free subjects, and that variance is ‘normal’ (Mannion et al., 2008; O Vasseljen et al., 2009). Furthermore, any delayed timing in chronic LBP patients has not yet been consistently found in subsequent research. Gubler et al. (2010) carried out a cross section study using ultrasound to time the onset of TrA during shoulder flexion in 48 patients with chronic LBP and 48 pain free patients. It was high quality, with little to no bias and suitable control and group allocation. They concluded that no difference exists between chronic LBP patients and pain free subject for TrA activation timing during shoulder flexion.

The second premise, that TrA training can improve delayed timing, also fails when testing. Ottar Vasseljen et al. (2012) carried out an eight week RCT (N=109) looking at one on-one core stability training versus one-on one sling exercises and group general exercises. Outcome measures were pain and disability, but also onset timing of TrA during shoulder flexion. They found that after 8 weeks of training there was no difference between groups on pain, disability and most importantly TrA onset timing with shoulder flexion. Generally it was a methodologically robust study with suitable power calculation, intention to treat analysis, low attrition and appropriate allocation. Unfortunately bias could have entered the study (in either direction, depending on the assessor’s preference), since the assessor was not blinded to group allocation during TrA timing analysis.

It can be concluded that; there is no consistent evidence chronic LBP patients have a delayed onset of TrA activation, any delay is not important to the causation of their LBP, and TrA training does not improve any timing issues.

Clinical Effectiveness

There have been many published research articles looking into the effect of core stability exercises in patients with chronic LBP, some higher quality than others. However, no randomised control trial has shown that core stability is more effective over general exercises for pain, function or disability in patients with chronic LBP. A 2008 systematic review which, included trials up to 2006, concluded that core stability exercises are unlikely to produce betters outcomes over other form of exercise (May et al., 2008).

Petrofsky et al. (2008) and Pensri & Janwantanakul (2012) state that core stability exercises reduced pain in chronic LBP patients, but with no comparison with general exercise, outcomes only taken on discharge and no subject allocation information, the results are inadequate to enable generalisations.

Ferreira et al. (2007) state that the short term effect of core stability is greater than general exercise for chronic LBP. They undertook a pragmatic RCT with 240 participants with chronic LBP of three or more months’ duration. They compared three different treatment protocols lasting eight weeks; general exercise, manipulation and core stability exercise. The general exercise group was a class based group involving general exercises based on the ‘Back to Fitness’ program by Klaber Moffet and Frost (Klaber Moffett et al., 2000). The core stability group received 12 individual treatment sessions over eight weeks based on Richardson et al. (1999), with the use of an ultrasound machine to aid in muscle recruitment and biofeedback.

At 8 weeks the core stability group had significantly better function, as measured by Patient-Specific Functional Scale (Westaway et al., 1998). However, pain and disability at eight weeks were the same in all groups. Furthermore, all outcomes at 6 and 12 months were similar in all groups. Pain was measured on a visual analogue scale, where 0 represents no pain and 10 worst pain imaginable, and disability by the Roland Morris Disability Questionnaire (RMDQ). This is an extremely reliable and valid outcome measure for pain, function and disability in chronic LBP (Beurskens et al., 1995; Roland et al., 1983).

The internal validity of Ferreira et al. (2007) is low. Intention to treat and sensitivity analysis were avoided. Coupled with a high, un-even, drop out rate, (9% for general exercise compared with 19% for core stability) this omittance lowers the robustness of the results and usefulness to the practitioner as it biases the results in favour of core stability. If core stability patients not having benefit from treatment drop out more frequently than the general exercise group their exclusion from the analysis would lead to an exaggeration of the effect of core stability.

Ferreira et al.'s (2007) short term results are contradicted by Koumantakis et al. (2005) study. Short term outcome measures at eight weeks showed core stability had significantly worse fear avoidance scores compared with general exercise on the Roland Morris Disability Questionnaire (RMDQ).

Koumantakis et al. (2005) had a slightly different methodology to Ferreira et al., (2007), comparing general exercises with general exercises plus core stability over eight weeks, and the general exercises were not based on the ‘Back to Fitness’ program by Klaber Moffet and Frost, (2000), but were non specific mat exercises.

Koumantakis et al. (2005) adjusted the total class time according to time of muscle activation, and as a result total class time for the core stability group was almost double that of the general exercise group (99 minutes v 180 minutes), biasing results in favour of the core stability group.

Koumantakis et al. (2005) had a larger attrition rate than Ferreira et al. (2007), however they carried out a sensitivity analysis, with intention to treat producing similar results to per protocol analysis, improving internal validity of results since this adjusts for the uneven drop out rates in their analysis.

Comparison and generalisation between these two studies may not be possible; the majority of patients for Ferreira et al. (2007) were unemployed, from low socio-economic groups whereas all patients for Koumantakis et al. (2005) were employed. It has been shown that people from low socio-economic groups are at a far greater risk of developing chronic LBP, and may have worse results with therapy (Katz, 2006). In addition, all patients for Koumantakis et al. (2005) must have had a x-ray or MRI to be included. It has been shown that patients who have x-rays or MRIs may have better short term satisfaction, but long term fear avoidance is generally worsened (Chou et al., 2007). Therefore, comparison of improvements in RMDQ scores between studies is of limited value.

Despite being unable to compare results directly, the higher internal and external validity ofKoumantakis et al. (2005) means we can trust the result more, and make generalisations better, which is further discussed in the conclusion.

Cairns et al. (2006) was another pragmatic, multi-centred, RCT comparing core stability exercises with conventional physiotherapy for chronic LBP. Both groups received 12 weeks of physiotherapy on a one to one basis, for up to 12 sessions. Both groups were allowed, if the physiotherapist felt warranted, manual therapy and electrotherapy. It was a comparatively high quality RCT, with power calculation, sensitivity analysis and a robust methodology. Attrition rates were high at 30%, but were comparable with Koumantakis et al. (2005), potentially indicative of patients with chronic LBP.

External validity of Cairns et al. (2006) as a stand alone RCT is low, since ‘distressed patients’ were excluded from the study, and it is known that many patients that present with chronic LBP are classified as distressed (MC Cairns et al., 2003). However, Cairns et al. (2006) included the RMDQ as an outcome measure, and in agreement with Koumantakis et al. (2005) and Ferreira et al. (2007) found no significant between group difference at 6 months and 12 months. Furthermore, they found short term outcomes were the same for both groups.

Although not statistically significant, the general exercise group had an improvement in 57% of patients, compared with 48% in the core stability group, and had a lower average number of treatment sessions. Cost was not calculated nor compared, but this finding is corroborated by Critchley et al. (2007) who did calculate cost in a comparison of traditional physiotherapy, with core stability and group pain management. Critchley et al. (2007) looked at the Roland Disability Questionnaire in 212 patients up to 18 months after discharged and found no difference between pain and disability in the three groups. However, cost was significantly lower for group rehab and traditional physiotherapy when compared with core stability.

These four trials are further strengthened by Lewis et al. (2005), Gladwell et al. (2006), Norris & Matthews (2008), Rasmussen-barr et al. (2009) and Muthukrishnan et al. (2010) who found that core stability training compared with control groups had no improvement in outcomes measures. Control groups being; group rehab, no treatment, information leaflet, daily walks and general physiotherapy respectively.

It can be concluded; there is some agreement that core stability offers no additional benefit in long term outcomes of pain, function and disability over general exercises, plus or minus other forms of physiotherapy treatment. It is likely to be more costly, and there is some evidence to suggest that fear avoidance in the short term may be worse.

Conclusion

This blog has questioned the relevant evidence surrounding the effectiveness and the underpinning physiological effects of core stability exercises for chronic LBP.

Despite being the most common form of physiotherapy treatment for patients there is a lack of evidence to support its use.

Any benefit over no treatment/minimal treatment can be attributed to the general exercise effect.

Core stability should not be used in patients with chronic LBP and a more general, functional,exercise regime used instead, as proposed by Klaber Moffet and Frost (Klaber Moffett et al., 2000).

References

Beurskens, A., De Vet, H., Van der Heijden, G., & Knipschild, P. Measuring the functional status of patients with low back pain: assessment of the quality of four disease-specific questionnaires. Spine 1995; 20: 1017–1028.

Bradford Hill, A. The Environment and Disease: Association or Causation? Proceedings of the Royal Society of Medicine 1965; 58: 295–300.

Cairns, M, Foster, N., & Wright, C. Randomized controlled trial of specific spinal stabilization exercises and conventional physiotherapy for recurrent low back pain. Spine 2006; 31(19): E670–81. doi:10.1097/01.brs.0000232787.71938.5d

Cairns, MC, Foster, N., Wright, C., & Pennington, D. Level of distress in a recurrent low back pain population referred for physical therapy. Spine 2003; 28(9): 53–9.

Chou, R., Qaseem, A., Snow, V., et al. Diagnosis and treatment of low back pain: a joint clinical practice guideline from the American College of Physicians and the American Pain Society. Annals of Internal Medicine. 2007; 147(7): 478–491.

Critchley, D., Ratcliffe, J., Noonan, S., Jones, R., & Hurley, M. Effectiveness and cost-effectiveness of three types of physiotherapy used to reduce chronic low back pain disability: a pragmatic randomized trial with economic evaluation. Spine 2007; 15(32): 1474–81.

Ferreira, M. L., Ferreira, P. H., Latimer, J., et al. Comparison of general exercise, motor control exercise and spinal manipulative therapy for chronic low back pain: A randomized trial. Pain 2007;131(1-2): 31–7. doi:10.1016/j.pain.2006.12.008

Gladwell, V., Head, S., Haggar, M., & Beneke, R. Does a Program of Pilates Improve Chronic Non-Specifi c Low Back Pain ? J Sport Rehabil 2006; 15(4): 338–350.

Gubler, D., Mannion, A., Schenk, P., et al. Ultrasound tissue Doppler imaging reveals no delay in abdominal muscle feed-forward activity during rapid arm movements in patients with chronic low back pain. Spine 2010; 15(35): 1506–13. doi:10.1097/BRS.0b013e3181c3ed41

Hodges, & Richardson. Inefficient muscular stabilization of the lumbar spine associated with low back pain: a motor control evaluation of transversus abdominis. Spine 1996; 21(22): 2640–2650.

Hodges, & Richardson. Altered trunk muscle recruitment in people with low back pain with upper limb movement at different speeds. Archives of physical medicine and rehabilitation 1999; 80(9): 1005–12. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/10489000

Katz, J. Lumbar disc disorders and low-back pain: socioeconomic factors and consequences. The Journal of Bone and Joint Surgery 2006; 88(2): 21–24.

Klaber Moffett, J., & Frost, H. Back to Fitness Programme: The manual for physiotherapists to set up the classes. Physiotherapy 2000; 86(6): 295–305.

Koumantakis, G. A., Watson, P. J., & Oldham, J. A. Supplementation of general endurance exercise with stabilisation training versus general exercise only. Physiological and functional outcomes of a randomised controlled trial of patients with recurrent low back pain. Clinical biomechanics (Bristol, Avon) 2005; 20(5): 474–82. doi:10.1016/j.clinbiomech.2004.12.006

Lewis, J., Hewitt, J., Billington, L., et al. A randomized clinical trial comparing two physiotherapy interventions for chronic low back pain. Spine 2005; 30(7): 711–21.

Liddle, S. D., David Baxter, G., & Gracey, J. H. Physiotherapists’ use of advice and exercise for the management of chronic low back pain: a national survey. Manual therapy 2009; 14(2): 189–96. doi:10.1016/j.math.2008.01.012

Mannion, A., Pulkovski, N., Schenk, P., et al. A new method for the noninvasive determination of abdominal muscle feedforward activity based on tissue velocity information from tissue Doppler imaging. J Appl Physiol 2008; 104(4): 1192–201. doi:10.1152/japplphysiol.00794.2007

May, S., & Johnson, R. Stabilisation exercises for low back pain: a systematic review. Physiotherapy 2008; 94(3): 179–189. doi:10.1016/j.physio.2007.08.010

Muthukrishnan, R., Shenoy, S. D., Jaspal, S. S., Nellikunja, S., & Fernandes, S. The differential effects of core stabilization exercise regime and conventional physiotherapy regime on postural control parameters during perturbation in patients with movement and control impairment chronic low back pain. Sports medicine, arthroscopy, rehabilitation, therapy & technology : SMARTT 2010; 2: 13. doi:10.1186/1758-2555-2-13

Norris, C., & Matthews, M. The role of an integrated back stability program in patients with chronic low back pain. Complementary therapies in clinical practice 2008; 14(4): 255–63. doi:10.1016/j.ctcp.2008.06.001

Pensri, P., & Janwantanakul, P. Effectiveness of Brief Education Combined with a Home-Based Exercise Program on Pain and Disability of Office Workers with Chronic Low Back Pain: a Pilot Study. Journal of Physical Therapy Science 2012; 24(2): 217–222. doi:10.1589/jpts.24.217

Petrofsky, J. S., Batt, J., Brown, J., et al. Improving the Outcomes after Back Injury by a Core Muscle Strengthening Program. Journal of Applied Reliabiltiy 2008; 8(1): 62.

Rasmussen-barr, E., Bjorn, A., Arvidsson, I., & Nilsson-wikmar, L. Graded Exercise for Recurrent Low-Back Pain. Spine 2009; 34(3): 221–228.

Richardson, Jull, Hodges, & Hides. Therapeutic Exercise for Spinal Segmental Stabilization: In Lower Back Pain 1999. Edinburgh: Churchill Livingstone.

Rivero-Arias, O., Gray, A., Frost, H., Lamb, S. E., & Stewart-Brown, S. Cost-utility analysis of physiotherapy treatment compared with physiotherapy advice in low back pain. Spine 2006; 31(12): 1381–1387.

Roland, M., & Morris, R. A study of the natural history of back pain, part I: the development of a reliable and sensitive measure of disability in low back pain. Spine 1983; 8: 141–144.

Tyreman, S. Causes of illness in clinical practice: a conceptual exploration. Medicine, health care, and philosophy 2006; 9(3): 285–91. doi:10.1007/s11019-006-9006-6

Vasseljen, O, Fladmark, A., Westad, C., & HG, T. Onset in abdominal muscles recorded simultaneously by ultrasound imaging and intramuscular electromyography. J Electromyogr Kinesiol. 2009; 19(2): 23–31.

Vasseljen, Ottar, Unsgaard-Tøndel, M., Westad, C., & Mork, P. J. Effect of core stability exercises on feed-forward activation of deep abdominal muscles in chronic low back pain: a randomized controlled trial. Spine 2012; 37(13): 1101–8. doi:10.1097/BRS.0b013e318241377c

Westaway, M. D., Stratford, P. W., & Binkley, J. M. The patient-specific functional scale: validation of its use in persons with neck dysfunction. The Journal of orthopaedic and sports physical therapy 1998; 27(5): 331–338. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/9580892

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28 thoughts on “Brace yourselves, we’re talking Core Stability with Ben Smith

    • Really well presented paper, thanks. Would be interested in ben’s view on whether the whole TrA concept is really just an evaluation of perturbation and has less to do with a concept of strength or stability?

      • Hi Neil

        Thanks for the comments.

        I personally find the whole concept of TrA quite abstract. TrA rarely comes into my thought process when assessing or treating patients.

        Thanks

        Ben

  1. Great analysis.I presume you are familiar with Eyal Lederman’s articie on this subject.
    Some of Paul Hodge’s recent research focuses on isolated TrA recruitment as a way of rectifying “smudging ” in the motor cortex.Any thoughts on this-i can provide references if you do not have them.

  2. There is work on’smudging’ after isolated work, but worth assuming this happens at a motor cortex level with any skill acquisition so I am not clear how valuable this is, I guess the link in overall function remains unclear , great point though

  3. Brilliant article, thank you so much for sharing it. Unfortunately Core Stability has become such a massive industry and consumers buy it, and providers love to sell it. Changing perceptions in the medical, health, fitness industries is what is needed, a massive undertaking but with articles like this we may just get somewhere.

  4. Interesting article. I don’t fully believe in solely TrA activation for trunk stabilization. I haven’t gone through all these articles but do they all just focus in TrA activation for trunk stabilization exercises or do they include the more generalized bracing tcehnique to activate the whole abdominal wall?

    • Hi Cathy, is there any difference in varying types of abdominal bracing, a brace is a brace, we cannot selective choose which Abdominals to use, also we know from anatomy studies that Trans Abs can be congenitally absent in some, so how can they brace something they don’t have. Finally why do we even need to brace at all, the Abdominals fire very well when doing ‘normal’ exercises, bracing doesn’t add anything, if anything it’s causes rigidity at inappropriate times and can be maladaptive in those with back pains

      Regards

      Adam

      • People are trying to selectivity activate TrA with the drawing in maneuver, also sometimes called hollowing. That is the primary way this muscle has been studied in early research and I agree that it is not functional to selectively activate the TrA. Bracing is required for every type of movement and if we don’t have the appropriate rigidity in the spine you get excessive lordosis or flexion that increases strain to the back. Hence spondys, disc herniations, etc. The amount of rigidity needs to be proportional the the activity and intensity. It’s not all or nothing. In normal people muscle activation becomes reflexive and automatic and we stabilize with activities like lifting or pushing without thinking. But in some patients with injury, pain or poor training they can be doing this incorrectly. Especially Pilates or other programs that tell you to pull your belly button to your spine and society is always telling people to suck it in. This creates poor stabilization and poor movement patterns thus increased strain to the spine. I agree pure trunk stabilization will not help with low back pain, it needs to be functional and proper training of an activity is needed to prevent low back pain. But some patients need to be taught how to stabilize first because they have been doing it wrong their whole lives. The goal is to make stabilization automatic. But you can’t expect someone to just do a sport or exercise and have proper form and stabilization.

        • Cathy, I totally disagree, conscious bracing is rarely needed, maybe when squatting with a few hundred Kg’s on your back or when about to receive a blow into the abdomen, or even when heavy lifting. But day to day, bracing doesn’t need to be taught or thought about at all during normal tasks and activities, and to ask someone to be braced or rigid at any intensity for normal tasks is erroneous.

          I’m also really concerned by your thoughts that a lack of bracing can cause a lack of stability and so disc herniations, spondys, it’s this simply incorrect thinking and NOT backed by evidence. These types of misconceptions can be harmful and produce fear, anxiety and more pain in many patients with low back pain, being told this by a therapist that they need to brace to prevent ‘damage’ or pathology is not good practice , please, please tell me you don’t tell patients this!

          Also I am also concerned that you state, people have “been doing it wrong their whole lives” first how do you know from seeing them a few times, usually when they are in pain, so moving differently, to make a MASSIVE assumption like that?

          Finally the goal to make stabilisation automatic is incorrect, stabilisation is automatic, without our interference, sometimes it’s affected when someone is in pain, but if we focus on reducing the pain and not the bracing by getting them moving and reducing their fear of movement the central nervous system will do the rest on its own, automatically.

          We, ie the physio profession, need to stop telling, informing our patients to brace, hollow, stiffen etc, it’s just not evidenced based or shown to help in any way!

          Regards

          Adam

  5. Hi all,
    I have to say my opinions have massively changed since I got involved with a much larger CLBP pool patients 3 years ago. All this research presented in this article is only a small proportion of hard evidence available that shows exactly what’s being said: not only you should stop bracing, but stop teaching bracing.

    I’m sure Cathy must be cringing while reading Adam’s comment (c’mon Adam be nice 😉 ) but unfortunately all of it is very relevant and critical. I was the first to feel hurt in my therapist feelings when exposed to evidence such as TvA activation is bogus, simply because I WAS TAUGHT this way years ago…

    When I started to look into the mechanisms of pain, specifically chronic pain, I started to veer away from “structural defects” and therefore “structural re-training” and have adopted a new ATTITUDE with my patients. Psycho-social factors are huge. Fear avoidance is huge. Patients beliefs are key and it is our role to learn how to identify those personal traits, try to diffuse / de-fuse them and avoid those big words “stability and control” unless carefully presented in a much larger context of well-understood and well-planned interventions.

    Get your patients to move, to train, to lift weights the right way, to enjoy physical activity, efforts and yes for sure wrap them up with core training but which involves MOVEMENT. Like Adam said, the rest takes care of itself.

    God knows it’s hard on the ego to be proven wrong, but we physios (I assume we are mostly physios here) have to embrace a much wider way to take care of those CLBP patients the right way. Who else will otherwise?

    All the best to you all, at the end of the day we’re all here for the same reason: to be better at what we do, right?

    Xavier

    • Hi Xavier

      Thanks for your comments, you present excellent reasons and are gracious and eloquent in your arguments, qualities I’m afraid I am not blessed with, as you can see/tell.

      If I have offend Cathy or anyone else with my blunt, dogmatic and opinionated comments I apologise, I can be like a bull in a china shop at times.

      But as you say the continued use of core stability, bracing type exercises needs to be eradicated from our profession and sometimes harsh, strong and blunt talking is needed to achieve this in my opinion

      Kind regards

      Adam

  6. Most parks right now offer tracks for individuals to walk on to get exercises.
    Back disc surgery is often done as a last resort after alternative treatments have failed.
    For best results, I recommend that you use
    real ice, place the ice over the injured disc (even if your pain travels – you need to get to the
    source of the pain), and leave it on for 15 minutes.

  7. A very interesting blog, but not really anything too new has been presented her. I think the key factor here (as you rightly mention) is how you define “core stability”? I certainly don’t define it in the bracing manner you describe above and none of the Physiotherapists working in my practice do either. So as you say it means “different things to different people” and before we go anywhere it really needs someone to properly define it. As you rightly say it is not about static contractions, but I believe more about the dynamic stability of the lumbo-pelvic region as people go about their everyday activities and sports. It’s about the interaction of a groups of muscles and not an isolated few.

    I have not read all the articles mentioned in the blog but the RCT trial that you refer to (May 2008) which concludes that core stability (presumably defined by the bracing procedure) exercises are unlikely to produce better outcomes that any other exercise is interesting. Did they produce similar outcomes as other exercise? Could they therefore justifiably be used for some patient groups? I think what’s important here is that isometric contractions are a valid form of strengthening. In the knee we do it all the time (Static quads), in tendinopathy (Purdam and Cook) we use it there too, but we don’t leave it there. We progress it.

    We never leave it with just these exercises (or shouldn’t). Interestingly the blog states that Ferreira et al (2007) found some short term outcomes with the TVA contractions which you might consider a basic static contraction. IF those exercises were then taken into function, loaded further as part of a progressive strengthening programme, could outcomes be even better? Was this done, or were subjects just left to perform the very low level work which arguable has very little functional relevance? How do the researchers assess the condition of people’s stability in the first instance before allocating them to groups? Why do we believe that a one size fits all approach is an acceptable research approach? (I could go on and will hopefully answer some of these question when reading!)

    I will read the articles to gather a more informed opinion, but as I say, I’m more a functional rehabilitator and rarely use the basic exercises unless I have people in a very poor state of condition. We all have good outcomes I’m sure using targeted exercise for individualised patient problems (in conjunction with other techniques) for all manner of lumbar spine problems. I would suggest that starting with a good definition of “core stability” is a good way to start. Some interesting thoughts.

  8. Hello,

    I thoroughly enjoyed this article. Conscise, clear and easy to understand.

    I am a student who is still getting my head around the topic of back pain and core stability. Could I enquire about a couple of things to satisfy my curious mind:

    1/ Adam, you mentioned in a comment above”we cannot selective choose which Abdominals to use”. Does this mean abdominal ‘hollowing’, where we try to selectively activate TA, rather than Rec abs is unfounded? I am curious as I am on an MSK placement, and today my clinical educator was trying to teach me hollowing. She said I wasn’t activating TA properly, I was only using Rec Abs, and this was something I had to work on and be mindful of when I teach this to patients? Is this not true then?

    2/ Is there any theory as to why patients in the study doing core stability exercises had greater fear avoidance in long run? Could it be they were being taught the importance of ‘hollowing’/ ‘bracing’ and were becoming fearful in daily life when they realised they could not sustain this?

    Thanks in advance and thanks again for posting this insightful article.

    • Hi Carol

      Sorry for the delay in replying been soooo busy but to answer your questions

      1/ you can always try and recruit selected muscles when and if u try hard enough, the question is does this matter, abdominal hollowing doesn’t have any robust evidence behind it as Ben has shown the notion of bracing the core by hollowing is an unnatural process it requires effort and concentration to do so and no signs of helping those with back pain or any other issue. Paul Hodges who back in the late 90s came up with the theory of poor trans ab recruitment and timing has now after more research found that this is flawed, as when you measure movement and muscle recruitment there are do many different variable and so many different ways the body and more importantly the CNS respond that we cannot say one way is better than the other, so I would tell you educator to get up to date with current evidence

      2/ yes increased fear is brought about throu poor explanations and advice by therapists when informing them incorrectly what core training is trying to achieve, telling people that there spines are loose or not supported and that they need to brace and contract all the time puts the ‘willy’s’ into people already fearful because of there back pain, we have to be so much more careful about the words we use than we ever do with the exercises we give as words can disable far more than an incorrectly performed pilates exercise

      Hope that helps

      Regards

      Adam

  9. Hi Adam,

    I was thrilled to find this article. This obsession about core stability has been on my radar for years. Perhaps more so recently since it is heavily emphasized in my current degree of chiropractic. We are taught how to instruct abdominal bracing/hollowing to our patients with low back pain who are to go through their daily activities while maintaining this intra-abdominal pressure. I cannot fully agree to this model, not only because I never saw the evidence for these claims but also from my personal experience. As a low back patient myself years ago, due to the abuse of volleyball since young age, I was told that my core was weak and it must be ‘engaged’ at all times (what ever that means). Of course, I did not listen to the ‘words of wisdom’ and instead kept with the lifting/training combined with soft tissue work on the hypertonic muscles. The pain was gone and it was not due to the constant contraction of the external sphincter. I do agree that weight training combined with other ways of therapy has a significant benefit to patient’s pain reduction, strength gains and overall wellbeing.
    The article used strong references which should be considered especially by current therapy programs and by therapists who keep promoting the idea of ‘Segmental Rolling Techniques’ for the engagement of the ‘inner core’ musculature.

    Thank you Ben and Adam.

    Regards,

    Marina

    • Hi Marina

      Many thanks for your comments, glad you found the article Ben wrote helpful

      This view however isn’t popular or widely recognised by a lot of physios and I think it is going to take a good few years before the core bracing and abdominal hollowing meme is eradicated from our profession

      Kind regards

      Adam

  10. Just reading through the comments….michael brownlow …i think your comments deserve to be acknowledged. Some very good points. Think real beneficial studies might compare outcomes of integrated treatment programmes and identify whether the inclusion of core training improves overall outcome. As you rightly point out treatment should be a progressive programme and maybe core training could have a role to play in some cases ….

  11. Hi Adam,

    First off, I wholeheartedly agree that trying to isolate the TA in an effort to stabilize the spine is futile and should be discarded.

    But I don’t agree when you say bracing doesn’t add anything, and should be eradicated in patient education.

    So we are on the same page, when I see the word “Bracing” I think of a coordinated isometric contraction of the abdominal wall (rectus, obliques) in order to stiffen the spine through contraction itself and an increase in IAP. And I consider the optimal way to brace is to increase IAP by taking a diaphragmatic breath against abdominal resistance with a neutral spine and pelvic floor contraction, to create a cylindrical “canister” of pressure a la DNS ideology. So when I say bracing from here on out, that is what I am referring to.

    I think the article itself was quite good in terms of debunking the TA hollowing myth, but a few things you mentioned on your comments bring me a little confusion.

    “Bracing causes rigidity which causes injury at inappropriate times”

    I agree to a point, when taken in context of which injury we are talking about. Not sure if you are familiar with the Joint by Joint model by Gray Cook (or regional interdependence), and I know there is no scientific data to support it outright, but I think it warrants consideration. It claims that as you go up the kinetic chain, each joint alternates between needing mobility and stability i.e. ankle-mobility, knee-stability, hips-mobility, L-spine-stability etc.

    As we are talking about low back pain, I can focus on the lumbar spine and its theoretical requirement for stability. If you have lost T-spine extension, and you have to put something overhead at any cost, and it requires spinal extension, its likely you will compensate by overextending at the L-spine, which can be a mechanism of injury.

    If you have lost mobility in the hips, and go to squat down deep for whatever reason, it is likely the L-spine will flex to accommodate the need for depth, and that combined with compression is a mechanism of injury as well.

    It makes sense with the myriad of research pertaining to core stability, that lumbar stability should be a priority.

    Granted I am still a student and don’t have any clinical experience, but in your clinic experience, do most lumbar spine injuries happen because the lumbar spine moves too much? Or because the lumbar spine doesn’t move enough?

    “Bracing doesn’t add anything” “Stiffness can’t help” “Bracing doesn’t need to be taught and should be eradicated”

    Bracing falls along a continuum of high threshold (squatting several hundred kgs) to low threshold (bending down to pick up a child), they vary in intensity but the principles are the same.

    You brace when you squat to promote a STIFF lumbar spine to avoid injury (usually resisting flexion) right? So why be loose in the lumbar spine doing everything else? Many repeated lumbar flexion movements with compressive forces can slowly “chip away” at discs, chronic overuse injuries can be just as problematic as acute ones.

    We can use running as an example as a need for lumbar stiffness. It involves repeated hip flexion, the psoas is a hip flexor, it attaches to the lumbar spine. If the lumbar spine isn’t being braced to some degree, when the psoas contracts and pulls on the spine, the spine will “give” and not only results in inefficient movement as some force is lost to pulling the spine forward instead of it all pulling on the femur. Depending on the magnitude of movement, it could rely on the passive structures of the lumbar spine (ligaments, capsule) to stop excessive motion.

    But if the lumbar spine is reinforced through an increase in IAP and contraction of surrounding musculature through bracing, it is better suited to resist the pulling force of the psoas, resulting in more efficient movement and less potentially harmful stresses on the passive structures.

    I 100% agree that exercise and movement should be prioritized when rehabbing essentially any injury, but if bracing should be eradicated would you not teach bracing to a patient with discogenic pain how to bend down properly by stiffening at the lumbar spine and hinging at the hips? It’s likely that to get a disc injury in the first place they were flexing too much at a segment, and over time or acutely they developed symptoms. How would you teach them how to go about their day (which probably involves bending over to pick something up at some point) without teaching them to stiffen their lumbar spine?

    They probably lost the intrinsic ability to stabilize their spine, would you not teach proper breathing patterns (which require slight contraction of the abdominal wall), and work with them on it, until it becomes easier and eventually becomes habitual?

    I admit I am biased because before my post grad studies I was a strength and conditioning coach and I am a competitive powerlifter so it’s hard for me take off my “Maximum performance” hat and put my “Injury Rehab” hat on. But good movement is good movement, it doesn’t matter if you are deadlifting 300 kgs or your toddler.

    I also realize I did not cite anything I have said, I am more than happy to go through the literature this weekend when I have more time.

    Thanks a lot,
    Adam

    • Hi Adam

      Wow thats a lot of questions and things to respond to, but here goes…

      First thing to say is I didn’t actually write this review this is Ben’s work, but I do wholeheartedly agree with his comments

      Next the bracing you refer to is the bracing everyone refers to, the abdominal hollowing is just another term for it, and either way the idea of needing isometric co contraction of the abs, diaphragm etc when doing many movements is simply flawed out dated and just not backed by ANY evidenced to help those with back pain

      Next I am biased too as an ex S&C Coach before I became a physio, and yes abdominal ‘bracing’ or splinting is great for some olympic lifting, but thats about its only use, for all other activities, tasks and sports its actually detrimental, and as I said before in those with back pain, it actually makes them worse, a lot worse.

      Next I am aware of Gray Cook and his FMS and SFMA and although some of his tests are ok, most are flawed and way to structured around an optimal mechanical movement paradigm that just doesn’t exisit, everyone and i mean everyone moves differently, we don’t fit into neat little SFMA boxes

      Stu McGills research and work on ‘super stiffness’ also is better but also in my opinion has some flaws in its approach, and Hodges work which started the Core Stability boom is also flawed and has been mis interpreted and Paul Hodges himself has been working tirelessly to try and correct this

      Next you state some causes of mechanisms of lumbar injury such as, over extending, increased compression, although yes, these can cause injury so can a lot of other things, and I haven’t read anything, anywhere that says one mechanism is more prevalent than another, thats if any mechanisms for lumbar pain can be traced at all, remember back pain is always multi factorial, its never due to one mechanism

      You also ask in my experience what i think causes more lumbar spine injuries, too stiff or too much movement, I say its not just that simple, again its multifactorial and I would say both are just as much of an issue, or not

      What I do know with my experience for what its worth, is those with back pain who are asked to brace and be stiff in the spine as they move and exercise, DOESNT help, and again I will say it, makes many far much WORSE.

      Next you use running as an example for a need of spinal stiffness, this is just not correct, yes there are phases of the gait that you need a stable stiff trunk, but there are just as many phases when you need flexibility and looseness of the trunk

      The ability of a ‘core’ of an individual to be stiff and stable when needed and then conversely relaxed and flexible is much more important and often forgotten and overlooked

      I hope this helps Adam, and i do understand that your views as a S&C coach here are skewing your views, I have been there, but the body just does NOT work the same when squatting 200kgs when compared to picking a toddler up as you describe, and we should NOT be looking to try and get everyone moving the same way or in the same pattern, instead multiple options of variability of movement, of stiffness, of flexibility is paramount and key to train and work towards, not bracing

      Cheers

      Adam

      • Hi Adam,

        What you say does make sense to me, I will definitely have to turn this info over in my head a few times to fully grasp it, but as a student I very much appreciate this blog to add another dimension to my studies and encourage critical thinking on my own.

        Thanks for taking the time to reply,
        Adam

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