IS RUNNING GOOD OR BAD FOR YOUR KNEES?

The belief that running is harmful to your knees started from past research studies showing the high forces undergone by the knee when compared to the forces during activities such as: walking, swimming, or cycling. Studies have shown that the forces through the knee during running are as high as 7.5x an individual’s bodyweight

By this logic, the suggestion to avoid running to protect your knees, or limit the number of miles you run due to wear & tear, was born. This belief was repeated so often that a 2022 survey found that over 50% of the general public believed that running long distances frequently led to an increased risk of osteoarthritis.

Cartilage Cells Can Adapt to Stress

Fortunately, this logic of force could induce wear and tear, and eventual failure simply does not hold up. Within reason, our bodies can adapt to the stresses placed upon them to build stronger and more resilient tissues. We have known this principle for some time in other structures, but we only recently gathered the evidence to truly support this principle in the case of cartilage. Resistance training or weightlifting depends upon this principle of adaptability. We stress our muscles, causing a state of micro-damage, and our body responds to this stress by building those muscles back up to be stronger & more resilient. In the case of our bones, they will adapt to the stress that they are placed under. For this reason, weight-bearing exercises such as walking are often necessary to prevent bone loss as we age, since the impact will force our body to respond by laying down more bone. A 2015 study using MRI scans showed that regular physical activity including running was associated with increased cartilage volume and reduced cartilage defects in middle-aged adults.

The scientific literature is unequivocally clear that when dosed and progressed appropriately, running is good for your knees. In fact, a 2017 study found that those who self-reported a history of being a runner were less likely to have knee pain as well as osteoarthritis. Additionally, a meta-analysis in 2017 found that recreational runners had a lower prevalence of hip and knee OA compared to sedentary individuals and competitive runners

The key to minimising the risks and maximising the benefits is implementing a gradual progression of load. In other words, the loads placed on your knee during running are not a problem, as long as you’ve worked your way up to that level of load.

References

1. Esculier J-F, Besomi M, Silva D de O, et al. Do the General Public and Health Care Professionals Think That Running Is Bad for the Knees? A Cross-sectional International Multilanguage Online Survey. Orthopaedic Journal of Sports Medicine. 2022;10(9). doi:10.1177/23259671221124141

2. Urquhart DM, Tobing JF, Hanna FS, et al. What is the effect of physical activity on the knee joint? A systematic review. Med Sci Sports Exerc. 2011;43(3):432-442. doi:10.1249/MSS.0b013e3181ef5bf8

3. Miller RH, Krupenevich RL. Medial knee cartilage is unlikely to withstand a lifetime of running without positive adaptation: a theoretical biomechanical model of failure phenomena. PeerJ. 2020;8:e9676. Published 2020 Aug 5. doi:10.7717/peerj.9676

4. Lo GH, Driban JB, Kriska AM, et al. Is There an Association Between a History of Running and Symptomatic Knee Osteoarthritis? A Cross-Sectional Study From the Osteoarthritis Initiative. Arthritis Care Res (Hoboken). 2017;69(2):183-191. doi:10.1002/acr.22939

5.          Prehab guys – Tommy Mandala

By Andrea Cutrupi, Chartered Physiotherapist.