Saturday, May 16, 2009

Knee Pain and Cycling

You ride your bike and and expect your knees to hold up - until they don't.

Knee pain for cyclists, previous injury notwithstanding, is usually not an isolated event; it is a process. We lose our health, knee joint included, one sand at a time until the point where we begin to notice it and do something to try and change the downward trajectory. Knee pain has truncated training rides, spoiled centuries and even ended cycling careers. But it doesn't have to - learn how to diagnose and prevent knee pain to keep cycling a part of your life for years to come.

What types of knee pain are common to cyclists?
Anterior knee pain which includes patellofemoral (also known as chondromalacia) is the most frequent type. Patellofemoral stress syndrome is an overuse injury that involves cartilage breakdown underneath the kneecap. Have you ever wondered why your knee makes crunching or popping noises going up or down steps? Often times this is a symptom of patellofemoral stress syndrome, because of an imbalance occurring above or below the knee. Some of this imbalance is caused by posture on the bike. Cycling positioning involves hunching forward and flexing your hips while in the saddle for long periods. If you are not fit to the bike properly this can exacerbate the problem. Other factors are muscle development distribution or a muscle strength deficit which can throw things off.

What causes knee pain in cyclists?
The knee can be affected by weakness of the gluteal external rotators which can lead to increased internal rotation of the leg and increase patellofemoral stress due to altered bony alignment. Cyclists typically have more developed calf and quadricep muscles than the average person. The vastus medialis is the tear drop shaped muscle that bulges out just above the inside of the knee and is usually well developed in cyclists, but if you have let riding go for a while or are new to the sport you can strengthen it with straight leg raises, lunges and dips or step downs with one leg going lower than the other while the other leg is on a block or stair. Other problems include muscle imbalances, excess motion in one or more joints, and leg length discrepancies. As we age a phenomena called cross linking occurs. This results in our tendons and ligaments being less flexible making them more susceptible to injury. Massage yoga and proper stretching can help minimize this. The body has a memory regarding injuries and sometimes it takes only a little more stress to setup for another injury episode.

Solution 1: Cycling Orthotics
A cycling orthotic can be made to compensate for problems that stem from too much motion occurring at the foot pedal junction.Not only can an orthotic decrease injuries but it can improve performance. This is accomplished by filling the dead space between your arch and the insole of your shoe so that energy is transferred directly to your pedal and not lost inside the cleat. An example of an imbalance which may be corrected is building lift on one side of an orthotic if there is leg length discrepancy. As a general rule, I usually compensate for half the difference of the discrepancy. Larger differences have to be adjusted in the crank arms or with shims. Another problem that can be addressed is excess motion, which can cause knee or arch pain. By placing a cant into a prescription for an orthotic, this force can be decreased. In cases where there are only minor issues over the counter insoles can sometimes be used.

Solution 2: Professional Bike Fitting
Bike fit issues and pedal selection may be the primary source or exacerbate existing knee problems. A saddle that is too high can lead to stress on the ITB, and patellofemoral loading can occur. If it is too low stress on the patella or quadriceps tendon can occur. If the seat is pitched too far forward stress on the anterior knee occurs because of too much flexion. If the saddle is too far back the ITB can be stretched because of the increased length. If the inside of your knee is bothering you and your clipless pedals have too little or no float, consider changing to a pedal with more float. If initial measures do not solve your problem a professional bike fit is in order. With this many moving - and connected - pieces, getting a professional opinion can not only increase your comfort and power, but also help ensure you can hammer for years to come.

Solution 3: Avoid the need for a Solution in the first place
Finally, try to control what you can. Keeping the knee warm in cooler weather is critical if you have any knee stiffness. Consider joining a yoga class or check out some yoga DVD's. Some people swear by glucosamine supplements to mininmize cartillage breakdown. Make sure you have no allergies to any of the components before you try glucosamine. If you have chronic swelling after exercise this may be a sign of more specific damage such as a meniscus defect or tear or internal ligament damage and a visit with your friendly neighborhood orthopedist is advised.

Remember that knee health is a process, not an event. Maintain your body more care than you put into your bike, because you probably use it more frequently and replacement parts aren't as easy to come by.