There is a groove in your knee that you kneecap is supposed to slide smoothly in. When it doesn’t stay in that groove, pain is felt around the kneecap. The pain is most evident when you sit for long periods of time, deeply squat, or walk up or down stairs.
The main cause of runner’s knee is muscular imbalance in the quadriceps muscles (front of the leg). There are four major muscles in the quads and for some reason (and there are many reasons that can cause this), one muscle is weaker than the others allowing the kneecap to slide improperly. There are many ways to treat this disorder depending on the origin of the disorder.
Many times, a simple exercise can cure or prevent knee pain. While doing a squat, on the first set, turn your toes inside but be sure to keep your knee over your toes. This strengthens the outside quad muscles. On the next set, turn your toe to the outside; this will strengthen the inside of the quads. On the final set, keep your toes straight ahead; this strengthens all the muscles equally. If you do this for about two weeks every other day, your knee pain might eventually go away.
Even if you are keeping up with strengthening, stretching, and proper footwear, there still is a chance your knee may give you some problems. At this point, you need to take into consideration your running stride as well as your training plan and surface. Over striding can be a cause of knee pain despite good strength and flexibility.
You have to put your body into a good, efficient position to be able to use the strength and flexibility that you have worked hard to obtain. Proper progression of training is important as well. The body needs time to adapt to the stresses of running. Running, and other exercise, causes a breakdown of the tissues in the body. Those tissues need time to repair themselves and become stronger, otherwise, injury occurs. Strength that you have developed in the gym, on the bike, elliptical, or in the pool is good, but running will still stress your body differently and you need to gradually increase mileage, frequency, and intensity of your runs.
A good rule of the thumb is to not increase your mileage by more than 10% per week. If you are not running on a regular basis, take a day off between runs until your body has adapted to running more regularly, even then, a rest day per week is good and necessary for recovery.
Lastly, don’t increase the intensity of your runs too soon. Get your body used to running before you start stressing it more with speed work and hills.
Many people ask if there is something they can put on their knee while they run to help them. I like to say “yes” and “no.” There are devices such as the Tendon Trak, patella tendon strap, KT Tape, and knee sleeves that can be worn during activity to help decrease the pain and symptoms of runner’s knee. While these interventions provide relief of the pain related to runners knee, they do not address or correct the underlying causes of the pain. I will suggest the use of these devices only if other measures are being taken to treat the condition and the runner wants something that will help them feel better on their runs so they can continue training.