The knee joint allows for fluid running and the cadence or turnover required for efficient running.  The knee is a modified hinge joint which means it has some accessory rotation which is allowed by the asymmetrical joint shape and muscular support. Knee pain in runners (collectively referred to as Runners Knee) is a symptom of an imbalance or breakdown in either the joint integrity or the muscular/connective tissue support structures. Below I will discuss ways to prevent and manage knee pain symptoms to reduce long-term injury implications:

Should I push through knee pain?
No.  Joint pain should never be ignored.  Unlike the burning quads and calves experienced late in a long training run or race, knee pain should be viewed as a warning which demands attention.  The knee joint is susceptible to torsional forces transferred from the ground (pavement, uneven trail surfaces, impact) and from the hips, core, and upper body.  In conjunction with the hip, the knee plays a key role in transitioning the impact of heel strike and shock absorption to the forward motion of the push-off phase of the running stride.  Pain in the knee, therefore, occurs when the muscular strength of the leg does not properly stabilize the leg     for proper knee joint mechanics.  Balanced quadriceps muscle strength is necessary for proper patella-femoral (knee cap) tracking.

Repetitive micro-trauma related to running with less than optimal strength and/or knee joint mechanics can cause accelerated cartilage wear.  Pain described as “dull and achy” is often a symptom of increased knee joint cartilage impact and/or wear.  Addressing the cause of knee pain early on can often prevent the need to take time off from running and more aggressive treatments and procedures.

Is running bad for my knees?
No.  Unless you have experienced prior knee trauma, have moderate to severe osteoarthritis, running is not bad for your knees.  A July 2013 study published in Medicine & Science in Sports & Exercise compared loads through the knee joint in separate samples of walkers and runners.  Runners typically place loads of eight times their body weight through the knee joint, while walkers place two to three times their body weight through the knee joint.  The key difference, however, lies in the duration and frequency of knee joint loading in runners versus walkers.  Running, the study concluded, loads the knee joint for a shorter period of time.  In addition, due to the increased speed of running compared to walking, fewer impact moments are experienced when running.  The overall impact of running versus walking was concluded to be the same over a given distance.  Walking has long been the exercise of choice for joint health.

Can I prevent running-related knee pain?
Yes.  Strengthening is the key to supporting the knee joint to allow the knee to do its job correctly and efficiently without pain complaints.  In order to minimize joint wear which can lead to osteoarthritis, joints need movement.  While excessive force and torsion through a joint can be detrimental, lack of motion as occurs in a sedentary lifestyle, can be even more harmful to joint health.  Loading and unloading a joint as the joint moves through its range of motion allows the joint to be “self-lubricated” by synovial fluid.  Running with efficient technique in the absence of past trauma or arthritis is an excellent way to insure joint health.  A real-time running gait analysis is a great way for a trained physical therapist to detect over-striding, leg movement pattern asymmetry, and running habits we do not detect in ourselves.
John Fiore, PT