At some time, one out of three cyclists suffers serious knee pain (Am J Sports Med, 2010 Dec;38(12):2494-501). It often occurs with a new bike, upon returning to cycling after a long hiatus, or when you are trying to increase either your intensity or your mileage. If your knee starts to hurt while you are on your bike, stop riding and try to find out the cause.
The most common cause of knee pain in bicycle riders is having the seat set so high that it forces you to fully straighten the knee as the pedal reaches its lowest level. You are never supposed to fully straighten your knee when you do any kind of exercise, particularly cycling or running. If you set your seat too low, you will bend your knee excessively and be at high risk for developing pain behind your knee cap. Other common causes of knee pain are over-training, setting your seat too far forward or backward, not having the cleats on your bike shoes set correctly, or not having the correct crank length.
Seat Height
Set your seat so that your knee is bent 20 to 30 degrees when one pedal is at its lowest level, and is not bent more than 70 to 80 degrees when the pedal is at its highest level. The ball of your foot should be directly over the pedal axle.
• When the seat is set too high: you can feel pain inside your knee, on the lateral side of the knee (iliotibial band), the medial back of the knee (pes anserinus tendon), or the lateral back (biceps femoris) of the knee.
• When the seat is set too low: excess bending of the knee causes the kneecap to rub against the femur, the long bone of your upper leg.Distance of Seat to Handlebars
When you sit on your saddle, you should be able to reach the brake hoods with your elbows slightly bent and relaxed. You can lean slightly forward, but you should not have to slide forward or back on the seat. Move your seat backward or forward so that when you sit on it, your tibial tuberosity (the bump on your lower leg just below the knee cap) is directly above the ball of your foot when the pedal is at its most forward position.
• When the seat is set too far back: you can feel pain on lateral side of the knee (ilio-tibial band) or back of the knee (hamstring tendons).
• When the seat is set too far forward: you can feel pain in the front knee cap (patellofemoral joint), the tendon just above the knee cap (quadriceps) or the tendon just below the knee cap (patella).Cleat Position
Pain on the inside or outside of your knee is often caused by setting your cleats so that your feet twist inward or outward.
• Cleats rotated too far inward can cause pain on the outside of the leg at the knee.
• Cleats rotated too far outward can cause pain and stress on the inside of the knee.
