That’s a huge percentage! Yes, according to recent evidence (Artero et al., 2012) running really does reduce the risk of death by 63%! As the title suggests this relates to cardiovascular disease and all-cause mortality (cause of death), which includes other chronic conditions such as obesity, diabetes and cancer. Lee et al (2014) identified that running less than 51 minutes a week decreased your risk of developing heart disease by 45% and all-cause mortality by 30% and persistent runners had the most significant benefits, with 29% and 50% lower risks of all-cause and cardiovascular mortality, respectively. 51 minutes a week! That’s less than 10 minutes a day and for the cost of a pair of running shoes, that’s an amazing deal and a cheap way to exercise! A more recent study by Hupin et al., (2015) found that moderate to vigorous activity in age groups of over 60 reduced all-cause mortality by 22%. So it’s good to start anytime.
So, we know that exercise is good.
Then something strange happens, we all understand that physical activity, be it running, cycling or swimming is good for us but somewhere along the line our understanding breaks down. Take running for example there are still some strong beliefs out there that running is bad for our knees. For years running has had a bad rep, compression is bad for your knees, that hard concrete surface cause too much compression on your joints and your cartilage wears away. You might be surprised to know that research as far back as 1985 has shown that running does not increase the risk of osteoarthritis (Panush et al., 1986; Sohn & Micheli, 1985).
So where did this conjecture come from? I suspect it came from our understanding of the classic metaphor ‘the body is a machine’. Like all machines over time they perish, wear out and parts need replacing. This idea that parts of our body wear out is still strongly entrenched in our understanding of how the body works. The defining factor here is pain. Our understanding of damage being equal to pain and vice versa. However, this understanding has also been shown to have poor correlation (Butler & Moseley, 2003), and of course no machines (cars, mountain bikes, drills, lawn mowers) that I know have a conscious ability to tell us when they are in pain. Humans though, we are pretty good at it. That’s another story.
Perhaps if we were machines, then we probably would wear out. The thing is we are pretty bloody special, pretty bloody amazing, and pretty bloody adaptable. The idea that our joints wear out is simply not true. It seems so strange how we rely on visual information to truly believe something. Take the muscular system for example. I think everyone would agree that the muscular system is highly adaptable, you only have to look at the chap in the picture to see that this is true.
Yet for some crazy belief perhaps the muscular system alone appears to have this exclusive ability to adapt over other body systems. So, when it comes to running or impact there is an understanding that our joints are going to wear out. Let’s put this nonsense to bed shall we.
A recent systematic review by Timmins et al (2016) found no correlation that running leads to osteoarthritis. Would it be any surprise that if it didn’t wear your knees out it would do the opposite? Well, that is what actually happens. Like our muscular system, cartilage in the knees, loaded in a graduated (just like we would do our muscles) adapts! Looking closer, the evidence suggests in sedentary individuals, 30 minutes of running ranging from 8-10km/h causes a decrease in cartilage thickness and volume, which then returns to normal after a period of rest (Niehoff et al., 2011; Subburaj et al., 2012).
Furthermore, a study by Mosher, Liu, & Torok, (2010) found that cartilage volume increased in response to running in younger and older marathon runners. Thus, it would seem that your cartilage actually increases in thickness and volume with running!
So, if 30 minutes of running increases the strength of your cartilage and less than 10 minutes of running a day reduces your risk of death then what effect does 10 minutes of running have on your cartilage? Well, common sense would hopefully prevail, I don’t know many non-runners than can do up to 30 minutes of running in one go, plus there is also the risk of injury due to our bodies not being adapted enough to running for this sort of time frame. So, the assumption would be that by just stressing your tissue even just a little bit is good for you, and we know this when we exercise. It’s good for our cardiovascular fitness. Oh look, another system that adapts when we partake in some form of physical activity.
If that wasn’t awesome enough for you more recent research (Belavý et al., 2017) has shown that running is even good for strengthening our lumbar discs!
The study by Belavy et al (2017) found that discs in long-distance runners and joggers had better disc hydration and increased glycosaminoglycans (GAGs) levels. GAGs are found everywhere in your body and have a really important role in the building blocks of all your tissues. Hydration is important (how ironic!) so a better hydrating disc means a stronger disc. This is exciting stuff, but with any new information it’s best to discuss with a health professional as we all have different circumstances. One size does not fit all!
I want to highlight here that this is not a reason to begin taking more supplements that claim to increase cartilage health or disc health as the evidence is really really sketchy around this stuff. Plus, it is common that people relate their joint health to pain and as I have said early the correlation around pain and damage is also sketchy.
I want to thank Jean-Francois Esculier (@JFEsculier on twitter) for inspiring me to write this blog. I recently attended his running course and got a lot out of it. It is certainly worth getting yourself a place on his course.
There will be more blogs coming from my reflections from the course soon.
I’m always keen to get other people’s thoughts on my opinions so please leave a comment below or on social media.
Thanks for having a read
Artero, E. G., España-Romero, V., Lee, D. C., Sui, X., Church, T. S., Lavie, C. J., & Blair, S. N. (2012). Ideal cardiovascular health and mortality: Aerobics center longitudinal study. Mayo Clinic Proceedings, 87(10), 944–952. https://doi.org/10.1016/j.mayocp.2012.07.015
Belavý, D. L., Quittner, M. J., Ridgers, N., Ling, Y., Connell, D., & Rantalainen, T. (2017). Running exercise strengthens the intervertebral disc. Scientific Reports, 7, 45975. https://doi.org/10.1038/srep45975
Hupin, D., Roche, F., Gremeaux, V., Chatard, J.-C., Oriol, M., Gaspoz, J.-M., … Edouard, P. (2015). Even a low-dose of moderate-to-vigorous physical activity reduces mortality by 22% in adults aged ≥60 years: a systematic review and meta-analysis. British Journal of Sports Medicine, bjsports-2014-094306. https://doi.org/10.1136/bjsports-2014-094306
Lee, D. C., Pate, R. R., Lavie, C. J., Sui, X., Church, T. S., & Blair, S. N. (2014). Leisure-time running reduces all-cause and cardiovascular mortality risk. Journal of the American College of Cardiology, 64(5), 472–481. https://doi.org/10.1016/j.jacc.2014.04.058
Mosher, T. J., Liu, Y., & Torok, C. M. (2010). FUNCTIONAL CARTILAGE MRI T2 MAPPING: EVALUATING THE EFFECT OF AGE AND TRAINING ON KNEE CARTILAGE RESPONSE TO RUNNING. Osteoarthritis and Cartilage, 18(3), 358–364. https://doi.org/10.1016/j.joca.2009.11.011.FUNCTIONAL
Niehoff, A., Müller, M., Brüggemann, L., Savage, T., Zaucke, F., Eckstein, F., … Brüggemann, G. P. (2011). Deformational behaviour of knee cartilage and changes in serum cartilage oligomeric matrix protein (COMP) after running and drop landing. Osteoarthritis and Cartilage, 19(8), 1003–1010. https://doi.org/10.1016/j.joca.2011.04.012
Panush, R. S., Schmidt, C., Caldwell, J. R., Edwards, N. L., Longley, S., Yonker, R., … Pettersson, H. (1986). Is running associated with degenerative joint disease? JAMA : The Journal of the American Medical Association, 255(9), 1152–4. https://doi.org/10.1001/jama.255.9.1152
Sohn, R. S., & Micheli, L. J. (1985). The effect of running on the Pathogenesis of Osteoarthritis of the hips and knees. Clinical Orthopaedics and Related Research, 198, 106–109. https://doi.org/10.1097/00004836-198410000-00013
Subburaj, K., Kumar, D., Souza, R. B., Alizai, H., Li, X., Link, T. M., & Majumdar, S. (2012). The Acute Effect of Running on Knee Articular Cartilage and Meniscus Magnetic Resonance Relaxation Times in Young Healthy Adults. American Journal of Sports Medicine, 40(9), 2134–2141. https://doi.org/10.1007/s11103-011-9767-z.Plastid
Timmins, K. A., Leech, R. D., Batt, M. E., Edwards, K. L., & Bchir, M. (2016). Running and Knee Osteoarthritis: A Systematic Review and Meta-analysis Running and Knee Osteoarthritis A Systematic Review and Meta-analysis. https://doi.org/10.1177/0363546516657531