Being evidence based is the rage, whether in the field of strength and conditioning, nutrition, or the world of training, corrective exercise, and rehab.

The question is should it really matter to you and what you're doing every day with your clients?

The simple answer to that is the evidence always matters!

It helps us sort through the mountains of opinions and personal experiences that we're bombarded with. It allows us to make informed, objective decisions on what we're giving to our clients and if it will help them achieve their goals.

This is much more important today, in the Internet and social media age. People can literally say whatever they want unchecked and often take advantage of this.

But the higher the level of evidence we demand, the more the onus is on those making claims about the dangers of X or the effectiveness of Y to give us some real proof behind the claims and opinions.

Let's take the world of corrective exercise for example. Corrective exercise is very specific in its aims, so it has to be able to fulfill them and provide evidence it can do so. The great thing is we have a whole bunch of evidence to help us!

Back pain

Lower back pain affects many people. This has led to a surge in courses, DVDs and articles that can teach trainers to perform postural assessments and prescribe corrective exercises for this problem.

But we must remember that just because a form of training, therapy, or rehab becomes popular does not make it right or "good science." Often science doesn't win popularity contests because it bursts the bubble of the many visionaries that populate health and fitness.

The great line "well it works for me" is no measure of scientific validity by the way.

How do we differentiate from the mountain of opinion and even paid for information in the certs and what we can actually prove that works? Look at the evidence -- after all, this is exactly what it's there for.

For a start, muscle activation patterns are varied to begin with (1). Do we have good solid evidence on what firing pattern should be happening in the first place or is it just hypothesis?

Before we attempt to correct something we should first know what to correct it too. How do we do know if we have reliable information on that? Look at the evidence.

Would you take a drug that they we're pretty certain in theory works but with no evidence to really know? I would probably steer clear!


So the big question then is what does the evidence say on whether "core stability" actually works for low back pain (LBP)?

A study looked at chronic back pain, (2) comparing core stability exercises with general exercise.

It found that although in the short-term core stability exercises did prove to be more effective in improving function and decreasing pain in the short term, over the longer term (6 months) there was no actual difference between the effects of the two.

This means that whatever stability issue it was proposed needed to be fixed a) wasn't or b) didn't affect LBP.  The short-term improvements could be tied to expectations placed on this type of therapy.

In fact, that is exactly what is discussed in a study (3) that compared Pilates with stationary cycling. Again in the short term the core based intervention was better, but in the long term not so much. The authors even posit that this short-term improvement maybe linked to the bias for receiving a clinically recognized treatment.

It is important not to just look at one piece of evidence. This is called cherry picking. So in the name of science let's keep digging.

Mannion et al. (4) found that a good clinical outcome is not associated with improved abdominal function. This means that someone's baseline abdominal muscle function and subsequent improvements made no affect on back pain. In fact people can get better with absolutely no change in their muscle function (5).

A study into exercise therapy (6) found that physical factors such as mobility, strength & endurance on the whole had no correlation with a positive outcome.

Do you even know if your client has poor "core stability" in the first place or have you assumed that because they have a backache this must be the case? This study found that 6 tests of core stability had poor inter (between testers) and intra (the same tester) reliability (7)

This doesn't mean that exercise isn't great for people with low back pain. Just a specific approach involving core stability such as getting the muscles to fire in a certain order or at a specific time is probably not helping as much as you think or have been told.

Improving core stability must help with performance then? A systematic review of the effects of core stability training on performance (8) found only marginal benefits.

Another study (9) looked at the relationship between the Functional Movement Screen, core stability, and performance. They found no correlation between core stability and FMS scores and that neither were good predictors of performance.

What about my tight hip flexors causing my back pain? Murrie et al. (10) found there was no difference in the lumbar lordosis of those in the study that had back pain and those that didn't. This was also the case in another study looking at the biomechanics of the same region between acute and chronic low back pain sufferers (11)

It's very difficult to reliably find out if someone has a pelvic tilt to start with due to the natural variation in human anatomy.

A study into the variation of anatomy between individuals (12) found that the natural variation present might significantly influence the measurement of a client's pelvic tilt.

So what about my glutes not firing or not firing in the right order? That must be a factor in my back pain?

This is the age-old theory of your glutes needing to fire before the other muscles when we extend our hip to stop hyperextension of the lumbar spine. But researchers actually found no consistent firing pattern -- instead (as we saw with the core firing patterns), muscle firing was variable across the subjects they studied (13)

The theory often proposed that the body is consistent in both its structure and the evidence does simply not support function. There appears to be no "correct" here.


What can we take away from this quick look at some of the evidence available to us?

Simply, it helps us determine if the theory we're being bombarded with in the industry has the proposed effect, and if it's based on solid science and evidence.

It doesn't matter about the perceived authority of the person saying it.

It does not matter if it seems to make sense to you.

At some point it has to be based in plausible science and evidence to back it up.

Why waste time on stuff that maybe ineffective when we could just get on and train people without worrying about trying to change stuff that doesn't have a beneficial effect!

With a little basic science and appreciation of the evidence base you can save yourself a hell of a lot of money and time.

Another major takeaway, apart from 'do your research', is about not making things worse. It's important to realize that what we tell people can have lasting effects.

Your clients trust you. Telling them their tight hip flexors or weak core will cause them back pain may have implications for how people feel about their bodies and what they're capable of doing. It might also just be down-right wrong.

If you continue to perpetuate ideas that have no scientific validity and you haven't even bothered to check them out then you're part of the problem yourself.

If the training industry wants to keep its credibility then we have to seriously up the game on the science front.

The more we demand it then the more it will have to happen.

What to do next?

The point of the article is not to suggest that everyone suddenly become researchers or spend all their time reading research articles -- after all there are people to train.

Instead start to follow the guys who are doing it for you. The Internet has some great research-led people. They're the ones who actually cite and reference science and research, not just spout their opinions.

Related Article

How to Analyze Fitness Research - Jonathan Fass

Here are some research led people to check out across the spectrum of health and fitness.

Alan Aragon - Nutrition (has a nutrition research review at

Paul Ingram - Myth busting/Injury

Todd Hargrove - Movement/posture


1 Vasseljien et al, Effect of core stability exercises on feed-forward activation of deep abdominal muscles in chronic low back pain: a randomized controlled trial. Spine. 2012 Jun. 1;37(13):1101-8

2 Wang XQ et al. A meta-analysis of core stability exercise versus general exercise for chronic low back pain. PLoS One. 2012;7(12):e52082.

3 Marshall P et al. Pilates exercise or stationary cycling for chronic nonspecific low back pain: does it matter? a randomized controlled trial with 6-month follow-up. Spine. 2013 Jul 1;38(15):E952-9

4 Minion A et al. Spine stabilization exercises in the treatment of chronic low back pain: a good clinical outcome is not associated with improved abdominal muscle function. Eur Spine J. 2012 Jul;21(7):1301-10

5 J Moreside et al. Temporal Patterns of the Trunk Muscles Remain Altered in a Low Back-Injured Population Despite Subjective Reports of Recovery.  Archives of Physical Medicine and Rehabilitation Volume 95, Issue 4, Pages 686-698, April 2014

6 Steiger et al. Is a positive clinical outcome after exercise therapy for chronic non-specific low back pain contingent upon a corresponding improvement in the targeted aspect(s) of performance? A systematic review. Eur Spine J. 2012 Apr;21(4):575-98

7 Weir A et al. Core stability: inter- and intraobserver reliability of 6 clinical tests. Clin J Sport Med. 2010 Jan;20(1):34-8

8 Reed C et al. The effects of isolated and integrated 'core stability' training on athletic performance measures: a systematic review. Sports Med. 2012 Aug 1;42(8):697-706

9 Okada T. Relationship between core stability, functional movement, and performance. J Strength Cond Res. 2011 Jan;25(1):252-61

10 Murrie V et al. Lumbar lordosis: study of patients with and without low back pain. Clin Anat. 2003 Mar;16(2):144-7

11 Nakipoglu G. The biomechanics of the lumbosacral region in acute and chronic low back pain patients. Pain Physician. 2008 Jul-Aug;11(4):505-11

12 Preece S. Variation in Pelvic Morphology May Prevent the Identification of Anterior Pelvic Tilt. J Man Manip Ther. 2008; 16(2): 113-11

13 Lehman G. Muscle recruitment patterns during the prone leg extension. BMC Musculoskeletal Disorders 2004, 5:3