Is running bad for your knees? by Paula Pappalardo

Do You Have Knee Pain When Running?

Understanding knee pain when running is crucial in preventing long-term symptoms.Patellofemoral pain (PFP) is defined as pain around or behind your kneecap. It is also referred to as “runner’s knee” due to its common occurrence in distance runners. ‘Runner’s knee' tends to be aggravated by activities that put increased load on your knee when it is in a bent position. These activities can include: stairs, squatting, jumping, and most importantly running.

What is causing your knee pain when running?

During running, the knee joint is placed under increased load of approximately 4 times body weight. This means that with each step, an 80 kilogram human will load 320 kilograms through the knee joint. It remains unclear whether it is the bone or tissues in the knee that produces the pain signal, nor is it important. What is important to understand, however, is the concept of homeostasis.

Homeostasis refers to a process of self-regulation whereby the body adapts to external conditions in order to maintain tissue health. In the case of the knee joint, as long as the load placed on the knee does not exceed the maximum capacity of the body to cope and recover from load, it will remain healthy. It is when a runner exceeds their maximum capacity that problems can occur.

To further simplify, let me give you an analogy. Imagine a person walking up a mountain. If they walk too high up the mountain and reach the peak, they will fall off the mountain. As long as the person stays below the peak, they can continue up and down the mountain. Once someone has fallen off the mountain, it is difficult to get back onto the mountain. The good news is, it is possible to get back onto the mountain. Knee pain when running is not an indication of tissue damage, but rather an imbalance between load and capacity.

What increases load?

Load can be increased by several factors such as increased speed and mileage, running up or down hill, and changing terrain and footwear. This does not mean that you need to avoid these changes in training, you just need to moderate changes. Generally, the body will tolerate an increase in load of up to 10%. This can be difficult to quantify, however, my recommendation is  to make gradual changes to your training.

What if I have not changed my load? Why do I still have knee pain when running?

Not only can increasing load change your maximum capacity, but maximum capacity can be reduced by psychosocial factors such as stress, anxiety, poor sleep quality and pain catastrophising.

How do I reduce my knee pain when running?

Let’s go back to the homeostasis theory. If we balance load with tissue tolerance we can achieve homeostasis and reduce your symptoms. If you are someone who increased load too quickly, work on reducing load with strategies such as avoiding hills, and reducing speed and distance in a single session. As your pain starts to settle, you can start to slowly increase load and ensure that your pain levels do not exceed 2/10. In contrast, if you are someone who has reduced their maximum capacity, working on improving sleep quality and reducing stress, anxiety and pain catastrophising can help.

How can a Physiotherapist help?

There is a strong evidence to suggest that strategies such as exercise rehabilitation, in particular for the quadricep, hip and trunk muscles, can assist in reducing short-term symptoms. Further, running retraining and modifying footwear can help reduce knee joint forces and improve symptoms. Physiotherapists are well trained in administering these interventions and help you get back on track without pain. Persisting symptoms should be attended to as soon as possible.  Symptoms that have not been managed for 3 months or more are more difficult to treat. More than half of all people diagnosed with runner’s knee report ongoing symptoms for up to 5 years. Therefore, it is important to get a review with an experienced Physiotherapist at the earliest convenience.

Warm Regards,

Paula Pappalardo

Director, Physiotherapist and Clinical Pilates Instructor

If you’d like to get in contact with Paula:

423 Station Street, Box Hill 3128

P. (03) 9899 8655 F. (03) 9898 9609