Early knee pain is usually painful when going up and down stairs, or when standing up after sitting for a long time, are significantly painful when bearing weight on the knee joint, because weight-bearing increases the friction of the knee joint. Therefore, patients with osteoarthritis of the knee joint should perform functional exercises without or with less weight bearing. Straight leg lifts: Patients with osteoarthritis of the knee who sit with their legs straight and their toes hooked upward and their heels not off the ground can sit with their legs straight and their heels on the ground so that their legs do not bear weight, then hook their feet upward and feel the tightness of the quadriceps above the thigh. This type of exercise is mainly to strengthen the quadriceps and reduce the pressure and wear on the knee joint during exercise. Most patients in the early stages have a more severe lateral patellar lesion because the lateral patellar ligaments are generally tighter than the medial ones, which yanks the patella outward during activity and wears the lateral side more severely. The strength of the quadriceps muscle is exercised through straight leg lifts, which can resist the strength of the lateral patellar ligament and keep the patella in a normal position, reducing joint pain when going up and down stairs. The squatting exercise: back against the wall, less weight, legs bent no more than 45 degrees squatting exercise is mainly for patients with early patellar cartilage injury, to allow the patella to adapt to the pressure of bending, but also to increase the strength of the quadriceps muscle, maintaining the patella in the normal trajectory of sliding. The specific practice is to squat with your back against the wall, so that the center of gravity backward to reduce the weight of the knee joint; do not squat too deep, bending the knee about 30 degrees is the best, the maximum do not exceed 45 degrees, squatting angle will increase the weight of the knee joint; two feet together or apart is okay. Do not squat too long, a squat 15 minutes ~ 20 minutes, a day in the morning and afternoon practice on the line. Older people should pay attention to the gradual process when practicing static squatting, slowly adapt to leaning against the wall.