First of all welcome to my third blog post! My name is Joe and I am a licensed Doctor of Physical Therapy and USA Track & Field running coach. I am also an avid runner, triathlete, and somebody who loves simplifying research to provide advice for endurance and strength athletes! I am excited to start writing new content for all my peeps trying to better themselves. Let's get straight into the topic of today which is " understanding arthritis and running".
Osteoarthritis (OA) and Running
I'd be a rich man if I had a dollar for all the times people said I should not run because it is bad for my joints. The statements can come in all forms but include:
" You will pay for that once you reach my age."
" Your knees are bone on bone, you can't run anymore."
" Run now and you will pay for it later."
You hear it all the time online and you might have heard it from friends and family. In one form or the other, people associate increased activity levels (especially running) with their knee pain. The most common culprit blamed is osteoarthritis. Terms are thrown around vicariously to describe it such as “bone on bone” and some healthcare professionals might tell you that you should never run again! This is basically a death sentence for any runner out there. What is fact and what is fiction?!
What is Osteoarthritis?
Before we try and understand the potential link between arthritis and running, let’s make sure we understand arthritis first. Arthritis can be classified broadly as either rheumatoid or osteoarthritis. We will be discussing the latter today. Osteoarthritis (OA) is a naturally occurring process by which age related changes occur to joints in the body, including the hip, knee, or shoulder. These age related changes appear when we take a picture of the joint, utilizing radiographic images or x-rays. Changes that may appear include osteophyte formation, decreased joint space, and reduced hyaline cartilage. Let me stress that these are normal changes and are surprisingly not associated with how you feel! What does that mean? Some people have joints that look nice and healthy on an image, but have TONS of pain. Other people can have the ugliest looking radiograph ever, which includes the famous “bone on bone” saying, and have ZERO PAIN. This means that you cannot understand or explain your pain simply through what shows up on one image. Capisce?
Some helpful images that summarize research studies below:
Why look at the research?
The reason we want to use research as a point of reference is because we cannot just rely on one individual experience. Research allows us to look at thousands of people with the same condition while also controlling for other factors like age, sex, occupation, and recreational exercise levels. This is why it is more valuable than relying on what a friend said or (sorry in advance) what your momma said. When I did my research while drinking an ice cold beer at my labtop, I was looking for the biggest studies that looked at osteoarthritis and its relation to prevalence to those with run competitively or recreationally. Let's take a dive into those studies to try to understand if their is a relation between the two and what you can learn through research articles.
Line them up and I'll knock them down
First study, let’s break it down. What we are looking at here is seventeen studies grouped together that looked at the occurrence of OA and its association with level of running (recreational vs competitive) and years of running.
The overall prevalence of hip and/or knee OA was:
3.66% in runners, 13.3% in competitive runners, and 3.5% in recreational runners.
3.03% in people running for less than 15 years and 17.2% in people running for more than 15 years.
Compared with the control group, recreational runners had a lower association with hip and/ or knee OA alone.
Compared with the control group, individuals with exposure to running of less than 15 years had a lower association with hip and/or knee OA in the overall population. Those running for more than 15 years had a higher association with hip and/or knee OA in the overall population.
When we look at those numbers of association of OA with running made earlier, you realize they are pretty low. Keep in mind these are just the general numbers that were not adjusted to reflect changes in Body Mass Index (BMI), workload (what a person did for their job), and previous injury across all the people included in the study. When they adjusted the data to include all these specific variables, the association of running with hip and/or knee OA could not be demonstrated. So as you can see, things are not as clear cut as we first thought. Some people run and have no hip/knee/ankle pain and feel great but they may have some images that show normal joint changes that are called osteoarthritis. Other people may have just begun their running journey and begin experiencing pain but may have minimal changes on their radiograph.
These numbers may seem surprising to some. The only takeaway is that people who have been running competitively for greater than 15 years may be at increased risk for radiographic OA. It is important to keep in mind that these are just numbers and do not mean you are doomed to a life of pain because you like to run. These studies only looked at the occurrence of OA and not the actual symptoms the people experienced. As we mentioned earlier, you can have a lot of structural changes without symptoms or vice versa.
Also when reviewing these seventeen studies, they were unable to determine what defined the amount of competitive mileage and therefore could not separate in each study which runners were recreational versus competitive. Furthermore, no study clearly defined what made somebody an elite runner! Is it somebody who runs 10 miles a week at a 5:40 pace? Do they run ultra marathons every day? Or only run marathons? So much ambiguity. The review concludes by stating " no information on the effects of recreational running for more than 15 years on the association with hip and knee OA is available." This is a fancy way of saying, we don't have the answer.
What does this mean for you?
Research is just that. It is the outcome when we try to control things as much as possible so we can make inferences on what this means for the general population. The article referenced above found an increased association between running and OA in competitive, but not in recreational, runners. BUT no study was able to find a clear link and they were also to unable to define the specific miles and intensity that made somebody competitive. The study also concluded that running at a recreational level was found to have a protective effect on hip and/or knee OA.
Does this put to rest those tall tales of running and activity being bad for your joints? Hopefully. I want you to understand that your body is designed to move. You are not defined by one image taken of your joints. You are not defined by your x-ray showing "bone on bone", your MRI, CT scan, or ultrasound. You are meant to walk, run, jump, or skip if that’s what makes you happy. So have no fear next time you put on those running shoes and head out for a run. You ARE NOT doing harm to your body by running. It actually can have a protective effect 😊.
Alright we accomplished a lot in a short amount of time! The big takeaways are:
Osteoarthritis is a naturally occurring process and it can and cannot be painful.
Taking a picture of your body does not tell the full story. You can have the perfect knee radiograph but have excruciating and debilitating pain!
A analysis that summarized seventeen studies was unable to determine if arthritis was directly caused related to running.
Running at a recreational level (whatever that means), can have a protective effect on the joints of the body!
Let me know what you think about this topic or if you have any questions you can comment below. Please share this blog post with a friend or fellow runner! We want to help out as many active individuals as possible. Like, comment, share, and happy running.
Keep Moving Forward!
Dr. Joseph Daigneau, PT, DPT, USATF-1
Lead Physical Therapist, Persevere Physical Therapy LLC
1. Chu Miow Lin D, et al Validity and responsiveness of radiographic joint space width metric measurement in hip osteoarthritis: a systematic review. Osteoarthritis Cartilage. 2011 May;19(5):543-9.
2. Silvis ML, et al High prevalence of pelvic and hip magnetic resonance imaging findings in asymptomatic collegiate and professional hockey players. Am J Sports Med. 2011 Apr;39(4):715-21.
3. Bedson J, Croft PR. The discordance between clinical and radiographic knee osteoarthritis: a systematic search and summary of the literature. BMC Musculoskelet Disord. 2008 Sep 2;9:116.
4. Kaplan LD, et al. Magnetic resonance imaging of the knee in asymptomatic professional basketball players. Arthroscopy. 2005 May;21(5):557-61.
5. 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 Jun;47(6):373-390. doi: 10.2519/jospt.2017.7137. Epub 2017 May 13. PMID: 28504066.