There are two reasons for patellofemoral pain after exercise: 1. local muscle ligament strain; 2. disorder of the patellofemoral joint and inaccurate alignment, resulting in pain from repeatedly hitting the surrounding tissues during exercise; after such symptoms are produced, the knee joint can first be given a brake, appropriate rest, local hot compresses, and topical blood-activating drugs. After the pain disappears, the quadriceps muscle, which is an important muscle to protect the knee joint, can be strengthened. You can also wear a knee brace to increase the stability of the patella.