The postoperative period after ACL reconstruction can be divided into 5 stages: compression bandage restriction period (within 1 week after surgery), activity restriction period (1-3 weeks after surgery), weight-bearing restriction period (3 weeks-6 weeks after surgery), activity recovery period (6 weeks-6 months after surgery), and activity enhancement period (6-12 months after surgery). 1 year before resuming strenuous exercise. Phase I: compression bandage restriction period (within 1 week postoperatively), exercise quadriceps contraction and straight leg raise under maintenance of compression bandage. Phase II: Activity limitation period (1-3 weeks postoperatively), active knee flexion 0 to 90 degrees without weight bearing under the protection of a movable brace. Phase III: Weight-bearing restriction period (3-6 weeks after surgery), under the protection of movable brace, walking with a single crutch, weight-bearing of the affected limb from 1/3 of the body weight, gradually increasing, and the crutch can be abandoned after 6 weeks. Phase 4: Activity recovery period (6 weeks-6 months after surgery), under the protection of movable brace, slow cycling and water walking to increase the muscle strength of quadriceps, gastrocnemius and N cord muscles. In addition, patients were instructed to perform proprioceptive training on a balance board or soft mat. Phase 5: Activity enhancement period (6-12 months after surgery), jogging without active brace.