There are three types of cartilage in the body: articular cartilage (also known as hyaline cartilage, covering the joint surface), fibrocartilage (such as meniscus, intervertebral disc), and elastic cartilage (such as external auricle). The surface of normal articular cartilage is smooth and blue-white, and the balance between the synthesis of cartilage matrix secreted by chondrocytes and the degradation of cartilage matrix is maintained, making the articular cartilage smooth and elastic, which can play important physiological roles such as protection, shock mitigation and friction reduction. In layman’s terms, articular cartilage, commonly known as “brittle bone”, when we chew chicken bones, pig bones, the white layer of “bone” in the joint area is articular cartilage, human joints are also covered by this layer of cartilage. Second, articular cartilage damage Articular cartilage damage refers to the damage of transparent cartilage covering the joint surface. With the increasing number of high-energy and high-speed trauma and the accelerated aging of the population, the number of patients with articular cartilage damage and degeneration is increasing. The development of articular cartilage damage to the final stage is the occurrence of osteoarthritis, that is, the people say Zhang bone spurs, osteophytes, osteoarthritis is also known as “age-related arthritis”, the occurrence of osteoarthritis and age-related, osteoarthritis is generally the problem of the elderly; in addition, osteoarthritis is also known as “This is the reason why the examination report describes “degenerative changes in the knee joint”. Simply put, the report “degenerative changes in the knee joint” indicates that the knee has arthritis, and the cause of this problem is the damage and degeneration of the articular cartilage. For early articular cartilage damage, superficial cartilage damage is usually not self-healing because of the limited ability of articular cartilage to repair and regenerate, while cartilage damage is deep to the bone and can be partially repaired by surgical treatment. Non-surgical treatment includes physical therapy, lifestyle changes (e.g., weight loss, reduced joint activity), and oral or injectable medications (e.g., pain medications, chondroprotective medications). Surgical treatment is mainly in the form of surface replacement of joints. (Professor Wang’s last issue was about “artificial knee surface replacement”) Fourth, prevention of articular cartilage damage because of daily life and sports are most likely to occur in the joint cartilage damage and degeneration. Therefore, it is important to protect such important articular cartilage from injury during sports and to avoid accelerated degeneration. First of all, grasp the exercise to “scientific and appropriate, depending on the person” the general principle, or as the saying goes: “what age to say what words. Must choose to adapt to their own age, with their own age should gradually choose some low-intensity sports, such as: walking, swimming, cycling and other sports. Secondly, before exercise to fully warm up. Make the flexibility, flexibility and coordination of the joints of the whole body to achieve an optimal state, to avoid injuries and diseases. Finally, it is not a single way to exercise, to diversity. Upper and lower limb exercise alternately, try to avoid choosing climbing, stair climbing and squatting and jumping as a daily exercise method.