Running is a complex activity despite the relatively simple explanation that it is a body moving quickly in a forward motion.

And when something is out of balance, runners most often complain of knee pain – often caused by a condition called runner’s knee. In fact, according to a 2013 article in Sport’s Health, runner’s knee can account for an estimated 40 percent of all knee pain complaints by runners.

“Running involves so many muscles, and the body is working in multiple planes,” said Jamie Lee physical therapist with PNW Physical Therapy. “To run properly and prevent pain, the body needs to be strong in many areas. Not just the lower legs, but the thighs, and hips, the core and arms.”

Some of the most common causes of runner’s knee include overuse, improper knee tracking or problems with the feet including improper running shoes.

Fortunately, runners can take steps to reduce their chances of experiencing (or re-experiencing) runner’s knee. According to Lee, they include:

  • Exercises to keep the core, hips and buttock muscles strong and healthy.
  • Stretching before and after a run. Dynamic stretches before a run (side shuffles, hopping, skipping) “wake up” the muscles and send a message to the brain that activity is about to start. After the run, do some long, static stretches to help prevent tight muscles.
  • Maintaining a healthy weight. Excess weight adds to the stress put on to the joints with each step.
  • Investing in the right shoes. Shoes designed for running and shoes that support the unique shape and character of an individual’s foot are essential.

If knee pain still becomes an issue, however, there are a number of ways to address knee pain, according to Lee. When a runner first experiences pain, he recommends they dial back their mileage and intensity and consider RICE.

However, if the pain persists beyond a few days, the runner might consider consulting a physical therapist.

The goal of physical therapy, according to Lee, is to determine what is causing the knee pain and look for ways to correct the movements that are placing extra stress on the knee and/or strengthen the muscle groups that are not adequately supporting the running motion.

Lee begins with an evaluation of the knees and lower extremities. His goal is to diagnose the cause of the pain. Is it runner’s knee or a meniscus tear or a ligament injury?

Next, he’ll videotape the patient walking, then running on the treadmill. The key is to view the running motion from different angles in order to break down the movements. By doing this, he can answer questions like is a hip dropping, is the knee in alignment with the pelvis and the second toe, is the core stable, how much force is the foot striking the ground with, and how is the foot landing?

“Any one of these or a combination of factors can disrupt a balanced running motion,” Lee said. “And if there is an imbalance, the most vulnerable joint is often the knee.”

Over time, as the knee heals and an exercise routine builds strength, the patient can gradually return to running. Lee recommends a few miles a few times a week, then gradually increasing running distance by about 10 percent a week – assuming there is no recurring pain.