Knee Pain - Part 2

In this second, three-part series on knee pain, I'm going to talk about some possible causes for knee pain. We'll go over a couple which are relatively benign, and which should make you call your doctor for an appointment immediately.

More than ever before, we as a human species are locked into a supported seated position with our hips and knees flexed to only 90 degrees thanks to chairs and raised beds. Most adults lose the ability to control their descent all the way to the point at which the hips meet the level of the knees, let alone past the knees into a full, deep squat. Yet, almost any child anywhere in the world up to the age of five has the ability to hit a full deep squat—feet flat, without the knees buckling inward, and without strain or pain.

Why do we lose those ranges of motion?

It's simple. Movement is a neurological process that requires practice for the brain to retain it. Put simply, "use it or lose it" is the essence of good mobility. Additionally, our bodies can change over time. Nutrients for tissue growth are allocated according to need and use. The less a range of motion is used under load, the less the muscle tissues that support those ranges of motion are nourished. Over time, with decreasing nourishment and mechanical stimulation, those tissues atrophy.

What this means for your knees is that the elastic connective tissues that span the knees need to be used through as full a range of motion as possible as consistently and naturally as possible for them to retain health. That also means that the joints neighboring the knees also need to be functioning properly. If your ankles have grown stiff and immobile from repeated injuries, from lack of movement, or from improper shoes, then guess what's making up for that lost range of motion—the knees.

The same can be said for the hips. When the muscles that control the hip don't have total ownership over the full range of motion, the closest neighbors (your knees and lower back) have to pay the price. So if your knees and lower back are aching after a workout, that may very well signify that you're not using your hips properly with safe technique.

In cases of traumatic injury directly to the knee, however, the body will shut down your ranges of motion to prevent the joint from being further compromised. So in the event of a jarring injury resulting in a meniscal tear, the knee may lock painfully. In the case of a torn ligament, such as the ACL or PCL, the knee may be unstable, causing the muscles around the knee to tighten abnormally to make up for the lost stability from the torn ligament. These sorts of situations require prompt professional medical attention. Even in the event of a malfunctioning knee mechanism that isn't structurally compromised, there may be pain in the system.

Generally speaking, any sharp pain or loss of passive range of motion means that something serious is going on with your knee, and it's a good idea to schedule an appointment with your doctor or a sports medicine specialist. Aching pains are a sign that things are already going wrong, but may very well be able to be arrested before things get to the point of injury with proper care and correction.

In the next article in this series, I'll cover some of the exercises and practices you can use to start restoring and optimizing your knees if they fall into some of the categories that do not require immediate medical attention. Remember, when in doubt, consult a medical professional to err on the side of caution. A good medical professional will explain your options and the reasons for his/her recommended course of treatment.

About the author: Dr. Mark Cheng holds a Ph.D. in Chinese medicine and acupuncture and is a California-licensed acupuncturist (L.Ac.). He blends ancient medical knowledge with modern sports rehabilitation science in his private practice. With an extensive background in martial arts, Dr. Cheng is also a Senior RKC kettlebell instructor, a faculty member for Functional Movement Systems, and a TRX Suspension Training Sports Medicine certified instructor. He has taught, lectured, and demonstrated around the world to fitness professionals, physicians, professional fighters, and military personnel. No other Beachbody^® instructor has ever brought the depth of credentials to the table like Dr. Cheng does.

Knee Pain - Part One

Knee Pain - Part Three