There are a variety of patients who need to perform squat exercises. Some have knee pain due to meniscal injury, ligament injury, cartilage injury, arthritis and other diseases, and have little weight bearing on the affected limb, resulting in muscle wasting atrophy, mainly quadriceps atrophy; others have muscle wasting atrophy due to prolonged post-operative braking of the knee joint or insufficient exercise. Regardless of the type, the static squat exercise is the most commonly recommended method of exercise. This action is similar to the Chinese martial arts “squatting horse stance”, in order to achieve good results, should bear in mind the following points: 1, stand against the wall, feet apart and shoulder width, toes forward, the upper body upright (do not learn upward); 2, at the beginning of the leg can be used to carry more weight, later can gradually increase the weight of the affected limb; 3, generally each time squat to the end of an inability to adhere to, rest 1 minute, and then repeat, can be repeated 3-6 times a day; 4, the existing research shows that 30 ° static squat patellofemoral joint pressure and upright when similar, 60 ° static squat is increased to upright 4 times, and 90 ° static squat is up to 6 times; so for people with patellofemoral joint cartilage injury static squat should not exceed 60 °, there is no above problem is best not to More than 90 °, otherwise it is easy to damage the patellofemoral joint not to mention the effect of exercise quadriceps; 5, without repeatedly squatting up and down, to maintain static.