Knee problems are common among all age groups. A clicking sound in the knee may indicate one of several issues. Overuse of the knee may irritate the bands of synovial tissue in the knee, called plicae, which can cause plica syndrome and clicking. Clicking may also indicate a tear in the meniscus cartilage on the sides of the knee or runner's knee, where clicking happens when you straighten the knee. So if your knee is clicking, see a doctor and perform exercises to correct weak or tight muscles.
Weak muscles in the thighs contribute to knee instability and clicking. Strengthening the quadriceps on the front of the thigh and hamstrings on the rear give the knee support. Also, stretching exercises for the iliotibilal -- or IT -- band relieve tension that could be pulling the knee to the side. The IT band is a fibrous band of tissue that runs along the outer thigh and down just past the knee. This tension is common especially for runner's knee. During recovery and to prevent further complications, always warm up before exercise. A warm-up can be simply marching in place. It is a way to increase your heart rate and warm up the muscles to make them more elastic.
Exercises that call for leg extension or a static contraction of the quads make these muscles stronger. An example is the quad-setting exercise. To perform quad setting, sit on the floor with both legs straight. Bend your left knee and put your foot on the floor as you place a rolled-up towel underneath your right thigh near the knee. Then, flex your foot and lift your heel and calf off the floor. Lower back down. Do not lift your thigh off the towel.
If the quads are significantly stronger than the hamstrings, there is a muscle imbalance that makes the knee vulnerable. The solution is to strengthen the hamstrings on the back of the thigh. Hamstring-strengthening contractions make the hamstrings stronger from a gentle lying-down position. Lie face up on the floor with your knees bent to 45 degrees. Lift your toes off the floor and press down with your heels, so that the hamstrings contract. Press down for five to 10 seconds and relax. As a general rule, the quads should only be 25 percent stronger than the hamstrings.
A strong, flexible IT band supports knee stability, but tension there pulls the knees outward. To stretch the IT band, cross your right leg behind the left as you stand up tall. Bend the left knee slightly as you lean to the left. Shift your hips to the right to increase the stretch and hold it for 30 seconds. Switch sides and repeat.