Pain over the knee joint while riding a stationary bike or after a long ride outdoors is not uncommon, especially if you're not used to riding a bike or if you've enjoyed a longer than usual bike ride. Knowledge of the structure of the knee and function of various muscles and ligaments in the knee joint may help you avoid such knee pain in the future.
Pain in the front portion of the leg just above the knee is a sign of distress or injury to the quadriceps tendon. This tendon connects the quadriceps muscle to the knee and down over the kneecap, where it inserts at the top end of the tibia or front lower leg bone. Pain may be aching and throbbing, caused by overuse and inflammation, or sharp and stabbing, caused by a ripped or torn muscle or ligament.
Several different muscles and muscle groups attach to the knee joint. Anterior or frontal knee pain caused by muscle strain to the distal or lower end of the quadriceps muscles and tendon may cause pain while placing forward pressure on the bike pedals. According to Get Body Smart, the rectus femoris muscle is a thick muscle that extends from the lower portion of the spine through the hip joint and down along the front of the thigh, where it inserts into the upper front portion of the knee joint. The quadriceps muscle and tendon are also located at the distal or lower end of the thigh and link to the knee joint.
Anterior knee pain while bike riding is caused by a number of factors, including improper seat height, bike speed or tension on gears as well as overuse of the knee joint before your bike ride. For example, if your seat is at a height that situates your foot too far forward on the pedal, you may place unwanted tension on the muscles located just above the knee. Slow pedal revolutions may also cause additional stress on the knee joint.
Adjust your bike seat when necessary for greater comfort. You'll have to ride a short distance to determine how your knee functions at various seat heights before you can determine the right height for you. Your knee should be flexed approximately 25 to 30 degrees when the pedal is at the lowest point. When possible, increase your speed or pedal revolutions to 75 rpm or above, suggests Cycling Performance Tips. Start bike riding on relatively flat and even surfaces to minimize muscle strain in the knee, and gradually add hills, dirt paths or uneven surfaces to your bike riding routine as your knees and thighs grow stronger.