The list of benefits from running are endless: improved cardiovascular health, lower risk of metabolic diseases, lower risk of a variety of the leading illnesses, improved cognitive function, increased ability to handle stress & anxiety, improved mental health, as well as the simple enjoyment of the “runner’s high” that is often cited. Yet runners are often given the warning by many that “running takes a toll on your knees”. This belief often stems from the assumption that repetitive impact can cause long-term damage by “wearing away the cartilage” in your knee, leading to osteoarthritis. However, the reality is much more complex, with research even suggesting that running can actually be good for your knees. This article will seek to definitively answer the question: Is running bad for your knees?

“Wear & Tear” on Your Knees; Myth or Truth?

The belief that running is harmful to your knees stems from research studies showing the high forces undergone by the knee when compared to the forces during activities such as walking, swimming, or biking. Studies have shown that the forces through the knee during running are as high as 7.5x an individuals bodyweight (1).

Thus, the assumption was made that greater forces through the knee would lead to breaking down of the cartilage in the tibiofemoral or knee joint. This cartilage serves as the cushion between the bones of our knee joint, making it the primary thing preventing our bones from rubbing together. That bone-on-bone contact is a phenomenon better known as osteoarthritis (OA). The development of OA is what can eventually lead to the need for an early knee replacement, thus protecting knee cartilage has always been a primary goal of medical professionals. This led many of them to recommend limiting the miles you run to protect your cartilage.

READ: BEST EXERCISES FOR KNEE OSTEOARTHRITIS

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 (2).

Does Increased Force Mean Wear & Tear?

Fortunately, this logic of force = 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, a principle known as Wolff’s Law states that natural healthy bones 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.

READ: RUNNER’S KNEE EXERCISES

Cartilage, however, due to its limited blood and nerve supply, has long been assumed to not adapt quite the same way as these other structures. However, recent evidence has shown that cartilage does adapt, responding to the cyclical loading of running by growing thicker & stronger.

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 (3).

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A different research group achieved the same conclusion by a different method. They used computer modeling to assess the probability of developing cartilage damage over a lifetime of running if cartilage were unable to adapt to the stresses placed on it (4). They then repeated the calculation under the assumption that cartilage was able to adapt to stresses placed on it. The model in which cartilage was able to adapt & grow in response to the stress of running showed a prevalence of osteoarthritis that was more comparable to the real-life prevalence of osteoarthritis in runners (13%) as compared to the 98% if cartilage were unable to adapt. This led the authors to conclude:

“medial knee cartilage is unlikely to withstand a lifetime of mechanical loading from running without a natural adaptation process, supporting the “cartilage conditioning” hypothesis for long-term joint health.”

Similarly, a 2022 meta-analysis of 43 articles showed that negative effects on cartilage from running were temporary, lasting a few hours, likely leading to long-term positive adaptations (5).

So is Running…Good for my Knees!?!

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 (6). While it’s tempting to point to the higher incidence of OA in professional runners as proof that individuals should limit their miles, this is likely indicative of a larger principle that anything done at a competitive or professional level involves a higher level of risk due to the inherent trade-off between short term competitive gains and long term health.

Running, like almost all other forms of physical activity, is good for you! The key to minimizing the risks and maximizing 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.

LISTEN: MANAGING RUNNERS WITH CHRIS JOHNSON

A 2014 study gives new runners a good general guideline by pointing out that novice runners who progressed their running distance by more than 30% over a 2-week period were significantly more likely to sustain an injury than those who increased their distance by less than 10% (7). So how can we begin to prepare our body for increasing our mileage and getting out there and enjoying all that comes with running? Check out the warm-up below to help prime your body for this type of movement before you head out on your run!

Remember that warming up and cooling down are important parts of any type of activity. Follow along as Craig demonstrates a few of his favorite exercises for a running warm-up.

Closing Thoughts

Running is actually good for your knees. When progressed gradually over time, running actually causes the cartilage in your knees to grow thicker and stronger, protecting you from the onset of painful osteoarthritis. Although, on a whole, running is good for your knees, starting a running progression and doing too much, too soon can certainly cause issues. This is no different than starting any other new workout plan. Giving your body time to adapt to the stresses you are placing it under is critical to obtain the benefit from any exercise, including running. A good general rule of thumb is to avoid progressing your running mileage by greater than 30% in any 2-week period.

Looking to take the guesswork out of progressing your body and being sure you are ready to crush that next race? Do yourself a favor and check out our Running Prehab Program below! See you at the start line!

LEARN MORE ABOUT OUR RUNNING PREHAB PROGRAM 

References:

1. Saxby DJ, Modenese L, Bryant AL, et al. Tibiofemoral contact forces during walking, running and sidestepping. Gait Posture. 2016;49:78-85. doi:10.1016/j.gaitpost.2016.06.014
2. 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
3. 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
4. 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
5. Khan MCM, O’Donovan J, Charlton JM, Roy JS, Hunt MA, Esculier JF. The Influence of Running on Lower Limb Cartilage: A Systematic Review and Meta-analysis. Sports Med. 2022;52(1):55-74. doi:10.1007/s40279-021-01533-7
6. 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
7. Alentorn-Geli E, Samuelsson K, Musahl V, Green CL, Bhandari M, Karlsson J. The Association of Recreational and Competitive Running With Hip and Knee Osteoarthritis: A Systematic Review and Meta-analysis. J Orthop Sports Phys Ther. 2017;47(6):373-390. doi:10.2519/jospt.2017.7137
8. Nielsen RØ, Parner ET, Nohr EA, Sørensen H, Lind M, Rasmussen S. Excessive progression in weekly running distance and risk of running-related injuries: an association which varies according to the type of injury. J Orthop Sports Phys Ther. 2014;44(10):739-747. doi:10.2519/jospt.2014.5164

About The Author

Tommy Mandala, PT, DPT, SCS, OCS, CSCS

[P]rehab Writer & Content Creator

Tommy Mandala is a Doctor of Physical Therapy, Board Certified Clinical Specialist in Sports & Orthopedics, and Certified Strength and Conditioning Specialist in New York City. He is the founder of ALL IN ACL, a digital coaching platform dedicated exclusively to helping ACLers return to the life they had before their injury with full confidence in their knee. Prior to that, he worked in the sports clinic at Hospital for Special Surgery, the #1 Orthopedic Hospital in the country. While there, he had the opportunity to hone his skills as an ACL specialist working closely with world renowned surgeons and evaluating patients from all over the world. He completed his sports residency training at the University of Delaware where he had opportunities to work with many of their Division I sports teams as well as the Philadelphia 76’ers NBA G-league affiliate, the Delaware Blue Coats. He also trained at Champion Sports Medicine in Birmingham, Alabama where he had the opportunity to learn from researchers in the American Sports Medicine Institute. Currently, Tommy works exclusively with ACLers through his digital coaching model. While many of these clients are athletes, Tommy works with ACLers of all different abilities helping them to build the strength they need to overcome this unique injury. One of his favorite aspects of his job is taking active clients who have never been a “gym person” before and showing them the amazing things that happen when they learn to strength train.

Disclaimer – The content here is designed for information & education purposes only and is not intended for medical advice.