Running causes "Wear and Tear" on your knees...Not!
You may have heard the term wear and tear when it comes to your joints. You may have been told by your doctor that you need to stop running because you have knee arthritis (OA), degenerative changes, narrowed joint spaces or that your knee is bone on bone.
MYTH – Running causes “wear and tear” and increased risk of knee OA
High quality studies have shown that runners and past runners have less radiographic findings and less symptomatic knee arthritis compared to non runners (Lo et al, 2017). Studies also show that running does not appear to be detrimental to people without knee OA (Timmins et al, 2017).
It is safe to say that running is a safe form of exercise to keep fit and healthy. Like most tissues in your body, cartilage become stronger when load is applied gradually.
But, I started running and developed pain in my knees
Firstly, congratulations to you for taking up a new form of exercise. You have managed to start something new and step out of your comfort zone. Give yourself a pat on the back.
There are multiple reasons as to why you may have developed pain during or after running. Please remember, pain is a warning system that is activated by threat or perceived threat. When you begin loading your tissues (muscles, joints, bones, tendons and ligaments etc) your body is being subjected to something foreign and may be perceived as dangerous initially.
Contributing factors of knee pain
It is clearly documented that pain is not a good predictor of tissue health. You may have increased your running duration/distance too quickly and did not accommodate for tissue adaptation and conditioning.
Your body needs time to strengthen and adapt to new stresses placed on it. Like any form of exercise, running needs to be introduced slowly and increased gradually over many weeks.
A good starting point may to run twice per week for 1-2km each run. This will allow time for recovery between runs also, which is critical to prevent overuse injuries.
Poor general strength and conditioning
When you run, your legs are exposed to forces of up to 8x your bodyweight. For example, if you were 80kg, your legs would need to tolerate 640kg of force for a continual length of time. If your leg strength does not match the physical demands, your risk of injury increases.
Most people are not aware that they have suboptimal leg strength when they start running. When deciding on how far or long you are going to run, you likely base the distance and duration on your past abilities. Unfortunately, your body is highly adaptable and you lose strength way faster than it takes to build it. So, if you have not been active for a month or two, do not be surprised at just how much strength and fitness you have lost.
Footwear (needs to match the individual)
There are four key design features in modern footwear today - cushioning, weight, support and stiffness. Different types of shoes are better matched to different types of running in terms of terrain, distance and speed. It is important to speak to a professional when choosing your shoes for running.
One of the biggest contributing factors to knee OA and pain is your bodyweight. Remember your legs are exposed to very large amounts of force for extended periods of time during a run. Even a 5% decrease in body weight makes a significant impact on pain and symptoms.
To reduce your risk of injury, it is highly recommended that you aim for a body mass index (BMI) of <25. To calculate your BMI, click here
But, I went to my doctor and was told to take painkillers and stop running
All current OA guidelines recommend physiotherapy as first-line therapy based on high level evidence for effectiveness (Brand 2014).
Unfortunately, despite recommended clinical guidelines, most people who present to their doctor with knee OA are prescribed medication as their first-line therapy and NOT physiotherapy.
Where to from here?
Physiotherapy can help you build up your strength and conditioning. Physiotherapy can help address other underlying factors such as stiff ankles or hips.
Management needs to take a holistic approach and will include other factors such as nutrition, stress, age and previous injury. There is never just one solution or a quick fix. Meaningful and lasting improvement requires time, consistency and a structured management plan.
Take home messages
Judge your condition by how you feel, not by what an X-ray says
Stay positive and hopeful
Lose weight (under supervision)
Exercise (under supervision)
Thank you for taking the time to read our blog. We hope you will continue running with confidence and longevity.