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The myth of the fabled runner's knee has haunted pavement pounders of all ages. However, a recent article in The New York Times has sought to defeat the specter of worn-out, arthritic knees on avid joggers. Apparently, not only will running not wear out your knees, it could even help protect them against arthritis.

A 2008 Stanford University study followed 500 longtime distance runners over 50 for nearly 20 years. At the study's onset, the runners ran approximately four hours per week, which declined to an average of 76 minutes per week after 21 years. Additionally, 6.7 percent of runners had mildly arthritic knees compared to none in an age-matched control group, reported The New York Times. Now, the old school of thought would lead you to believe that after 20 years, runners experienced a higher incidence of arthritic knees. In reality, the reverse happened. Only 20 percent of runners experienced arthritic knees compared to 32 percent in the control group.

Researchers think that running may be able to shield the body from arthritis because the knee develops a kind of motion groove, wherein the knee joint adapts to the action of running.

"What people have to be concerned about is prior state of the knee when running," says Timothy E. Hewett, orthopaedist and spokesman for the American College of Sports Medicine. "If you've had a prior ligament injury where the knee has already pushed toward osteoarthritis, running on that knee may accelerate it. However, if it's healthy and never been injured, the newer findings are more correct that a healthy knee is not going to be damaged by running."

The important thing to remember, notes Hewett, is that runners need to take cues from their body. "If they have knee pain or if they have swelling, they can be potentially damaging their knees. Swelling after running is a very bad sign because it can damage the knee joint. In addition, because there are no nerve endings in the cartilage, any knee pain experienced post-running means that the cartilage is being shocked enough to hit the bone. If you experience either, Hewett strongly urges you to take time off and do an activity with less impact, such as using the elliptical or swimming.

While you may not start out with bad knees, it's possible for them to wear down if you don't take proper precautions. For example, instead of running on pavement or concrete, which can cause shockwaves to come up through your joint, run on grass, dirt or a rubberized track. "Each time you hit the ground, the ground hits you back with equal and opposite force," says Hewett. That force is compounded by momentum and velocity, which can result in a force that's two to five times your body weight.

You know that favorite pair of running shoes parked next to the front door? OK, well, not only do they smell like wet dog (trust us, they do), but they're also bad for your knees. "Your average running shoe only has so many runs in it," says Hewett. "On average, you're in the range of 1,000 miles on a pair of shoes, and that's excessive. They start breaking down after 500 miles and people don't take that into consideration." You don't have to throw out your favorite pair of sneaks -- retire them to the world of gardening if you want -- just don't run in them.

There are other issues, such as biomechanics, that can play a role in how healthy your knee joints remain. For example, flat-foot hitting or tilting the pelvis side-to-side can affect neuromuscular balance and speed up any potential knee injuries. However, you should try the simple things first, such as running on softer ground and changing up your shoes, before getting your biomechanics analyzed. The important thing to remember is to listen to your body. "What you don't want to get into is a position of pain or some imbalance," says Hewett. "That usually leads into a vicious cycle, and you need to disrupt that cycle as early as possible."

Suffer from aches and pains post-run? Consider Chi running, a new method that corrects form and posture, which can prevent sore joints and muscles.