Running Related Injuries Part II: Knee Pain
What is "runner’s knee"?
Runner’s knee is pain at the front, side or right behind the kneecap. Medically it is known as patellofemoral pain syndrome but is better known as “runner’s knee” thanks to its prevalence among runners. It often starts as a slight pain in your knee while running but progresses to more severe pain that lingers after your run and finally starts affecting your daily life of walking up/down stairs. Doing exercises that involve bending the knee (squats, lunges) can sometimes cause the same pain, so it is not always just runners who are affected. A tell-tale sign of runner’s knee is more pain when you are going downstairs or descending steep hills.
The good news: Runner’s knee is not a structural problem, meaning your ligaments and cartilage are fine. The problem lies in how your muscles function through the repeated movement of a run or knee bend. The pain is caused by the kneecap moving in an abnormal way as you bend your knee. You might often hear clicking in the knee. The most common culprit of this uncomfortable rubbing is muscle weakness and tightness around the legs and pelvis.
Why it occurs?
Runners often have strong hip flexors and usually weaker posterior hip muscles, like the gluteus medius. They can become very knee dominant. Knee dominance is when your initial bending motion starts from the knees. The knees tend to go much further over the ankles when you bend your knees. The hips tend to go in a straight line downwards as opposed to bum back and down. People who are knee dominant movers generally feel leg exercises mostly working the quadriceps, which overtime can put the knee under more pressure hence why it may become painful sooner. Also, it means that the quadriceps are doing majority of the work instead of the glutes.
How to fix it?
Strengthening these posterior muscles (glutes, hamstrings, calves) will help to improve the imbalances. Studies show that when the glutes are strong and firing efficiently that it not only optimises performance, but also can decrease your risk for injury in the knee as well as other parts of your body.
Try to become more hip dominant. Your physio or coach will be able to help you with this. Hip dominant movement is when your initial bending motion starts from the hips. During hip dominant movements, the hips go back and down as if sitting into a chair. Knees stay in line with the ankles or slightly over (which is fine). Hip dominant movers typically feel the exercise work the glutes (posterior chain) more than the quadriceps which are much better at handling load and much more powerful when trained correctly.
Core exercises. As we run our legs can become heavy as our pelvic stability falters. Too much movement occurs around the pelvis making our legs carry a greater load each time they move. Do you find after a certain distance you don't feel as light on your feet, you start to lean forward and/or your legs become heavy? This is the postural muscles in your pelvis, abdomen and back fatiguing. Often referred to as your "core". As these muscles strengthen you will become a more efficient and lighter runner for longer distances.
Pilates is a great way of strengthening these muscles and in Pilates, they work on isolating certain muscles groups in the legs individually so that any muscle imbalances are minimised.
Manage running volume correctly. Often knee pain can occur from a change in running volume. This means the distance or speed of your running has increased too quickly. For example, you may have taken a three week break from running because you were on vacation and then gone straight back to running 50km a week. Consistency is key when it comes to running volume and preventing injury. We recommend you follow the 10% rule when it comes to running volume. That means not increasing your weekly total kilometres by more than 10% each week.
When to see a Physiotherapist?
If there is any swelling at the knee joint, get it checked by a Chartered Physiotherapist. They can pinpoint exactly what is causing the issue and rule out any structural damage, as well as provide a gait analysis to help improve your run mechanics. Also, if you experience the pain and start doing the above-mentioned strengthening work, and it doesn’t improve in a few weeks, then it’s time to see a Physiotherapist
While lots of runners do get knee pain, that doesn’t mean it’s just something you have to deal with on a daily basis. Don’t feel like you have to run through it. Seek advice from a professional to nip it in the bud.