PainSci summary of Belavý 2017?This page is one of thousands in the PainScience.com bibliography. It is not a general article: it is focused on a single scientific paper, and it may provide only just enough context for the summary to make sense. Links to other papers and more general information are provided at the bottom of the page, as often as possible. ★★★★☆?4-star ratings are for bigger/better studies and reviews published in more prestigious journals, with only quibbles. Ratings are a highly subjective opinion, and subject to revision at any time. If you think this paper has been incorrectly rated, please let me know.
More good (and counter-intuitive) news about intervertebral discs. It’s like spinal Christmas!
Last week I shared the science news that at least half of herniated discs spontaneously “de-herniate,” and that it’s actually the worst herniations that are the most likely to resolve (Zhong 2017, Chiu 2015). Nice to know.
Today’s news is that running may be good for your intervertebral discs, rather than being hard on them. It makes them bigger and juicier! For decades, almost everyone has assumed that the jarring impact of running constitutes a source of relentless wear and tear on the spine, and that the discs in particular probably cannot keep up with the onslaught, and aren’t able to adapt and recover — a slow losing battle. Specifically, data on “turnover rates” — how quickly tissue is replaced — have “lead to the assumption that positive adaptation in the mature intervertebral disc is unlikely to occur during the normal human lifespan.”
This new evidence, the first of its kind, suggests exactly the opposite: “tissue adaptation will occur in the intervertebral disc with exercise.”
Some differences between non-runners and runners were quite striking. Discs were much “juicier” in runners: “better hydration and glycosaminoglycan content” by a wide margin. Discs were also thicker in runners, but only a little. These results were found in runners aged 25-35 with a five year history of running at about the same level, and the benefits were slightly greater in long-distance runners (more than 50K per week).
The researchers collected additional data from 10 runners and identified an important caveat: the improvements were most strongly associated with “fast walking and slow jogging.” The link weakened at both slower and faster speeds (under 1.5m/s and running over 2.5m/s), or with high-impact jumping. The benefits were also not clearly related to overall activity levels. More was not obviously better. It was a just-right intensity of the stimulus to the discs that mattered.
In other words, you do not have to be hardcore to get these benefits! “It is possible that high volume or intensity running is not required for a beneficial adaptation.”
One final pleasant surprise: the lumbar spinal discs were in especially good shape in runners.
Despite repetitive loading of the spine during running, the exercise groups of the current study did not show any detrimental effects at these lower lumbar segments. In contrast, the long-distance runners and joggers showed evidence of better IVD hydration and glycosaminoglycan content in the lower lumbar spine than those that did not perform sport. Furthermore, the evidence for IVD hypertrophy subsequent to habitual running was strongest at the lower lumbar levels. Our data show that repetitive axial loading of the spine under body weight during running in otherwise healthy people may well be beneficial for the lower lumbar IVDs.
All very nice to know.
original abstract†Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
There is currently no evidence that the intervertebral discs (IVDs) can respond positively to exercise in humans. Some authors have argued that IVD metabolism in humans is too slow to respond anabolically to exercise within the human lifespan. Here we show that chronic running exercise in men and women is associated with better IVD composition (hydration and proteoglycan content) and with IVD hypertrophy. Via quantitative assessment of physical activity we further find that accelerations at fast walking and slow running (2 m/s), but not high-impact tasks, lower intensity walking or static positions, correlated to positive IVD characteristics. These findings represent the first evidence in humans that exercise can be beneficial for the IVD and provide support for the notion that specific exercise protocols may improve IVD material properties in the spine. We anticipate that our findings will be a starting point to better define exercise protocols and physical activity profiles for IVD anabolism in humans.
- “Incidence of Spontaneous Resorption of Lumbar Disc Herniation: A Meta-Analysis,” an article in Pain Physician, 2017.
- “Resolution of Lumbar Disk Herniation without Surgery,” a webpage on NEJM.org.
- “Progression of lumbar disc herniations over an eight-year period in a group of adult Danes from the general population: a longitudinal MRI study using quantitative measures,” an article in BMC Musculoskeletal Disorders, 2016.
- “Magnetic resonance imaging in follow-up assessment of sciatica,” an article in New England Journal of Medicine, 2013.
- “The probability of spontaneous regression of lumbar herniated disc: a systematic review,” an article in Clinical Rehabilitation, 2015.
- “Systematic Literature Review of Imaging Features of Spinal Degeneration in Asymptomatic Populations,” an article in AJNR Am J Neuroradiol, 2015.
- “MRI Findings of Disc Degeneration are More Prevalent in Adults with Low Back Pain than in Asymptomatic Controls: A Systematic Review and Meta-Analysis,” an article in AJNR Am J Neuroradiol, 2015.
These three articles on PainScience.com cite Belavý 2017 as a source:
- PS Is Running on Pavement Risky? — Hard-surface running may be risk factor for running injuries like patellofemoral pain, IT band syndrome, shin splints, and plantar fasciitis
- PS Save Yourself from Low Back Pain! — Low back pain myths debunked and all your treatment options reviewed
- PS Tissue Provocation Therapies — Can healing be forced? The laws of tissue adaptation & therapies like Prolotherapy & Graston Technique
This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog. A few highlights:
- A Bayesian model-averaged meta-analysis of the power pose effect with informed and default priors: the case of felt power. Gronau 2017 Comprehensive Results in Social Psychology.
- Association of Spinal Manipulative Therapy With Clinical Benefit and Harm for Acute Low Back Pain: Systematic Review and Meta-analysis. Paige 2017 JAMA.
- Incidence of Spontaneous Resorption of Lumbar Disc Herniation: A Meta-Analysis. Zhong 2017 Pain Physician.
- How much is too much? (Part 1) International Olympic Committee consensus statement on load in sport and risk of injury. Soligard 2016 Br J Sports Med.
- Chiropractic spinal manipulative therapy for migraine: a three-armed, single-blinded, placebo, randomized controlled trial. Chaibi 2016 Eur J Neurol.