If the knee pain after exercise is short-lived pain, it may be due to excessive exercise load resulting in joint ligament, tendon, cartilage and other strain caused by soreness, after rest can be slowly relieved by itself. If there is frequent pain in the knee after exercise or for a long time, it may be due to the following factors: 1. improper force or excessive exercise, resulting in damage to the knee ligaments, meniscus, cartilage wear and other causes of pain. 2. the existence of chronic strain injury of the knee joint capsule ligaments, etc., after the movement of local tissue edema, spasm, resulting in obvious pain symptoms. 3, In middle-aged and elderly patients, degenerative changes or osteoarthritis of the knee joint lead to significant osteophytes or degeneration of the cartilage meniscus, causing significant pain during exercise.