1.Prerequisites: ① Not too old. Young and middle-aged people are eligible. ②The diagnosis of chondromalacia patellae was confirmed in a professional hospital, and after five weeks of regular treatment with intra-articular injection of sodium hyaluronate and oral glucosamine, the reduction of activities was in place during the treatment period. ③There is a certain amount of knee dysfunction left after treatment so far, and there is a certain amount of swelling response to static squatting. 2. The following strategies should be followed for recovery: Practice function first:i.e. dysfunctional practice, but swelling will occur after each exercise, and swelling can be reduced by the following three items. ① practice every two days; ② control the duration of each exercise to 5-10 minutes; ③ each time there is 1-2 ° progress; ④ reduce other activities such as walking; ⑤ ice after each exercise. Quiet Squat:There is no hope for the knee joint if you don’t practice quiet squatting and your muscle strength can’t get up. Only if you practice quiet squatting and your muscle strength improves significantly will you have a chance of getting better. Don’t forget that quiet squatting shouldn’t cause too much wear and tear on the knee joint, and even if you have some reaction after practice or some pain after practice, you should stick to it until your muscle strength improves.