Some elderly people believe that: climbing stairs can prolong life, each climbing a step, live 4 seconds more. However, we often see people struggling on the stairs, knee pain to no way to go upstairs, and even the more climbing knee problems more serious. So, is climbing stairs or hiking a good exercise or not? As an arthroscopist, I don’t deny that stair climbing or mountain climbing has many advantages, such as enhancing cardiopulmonary function and burning calories, but the disadvantages are so severe that they really outweigh the benefits. That’s why I never advise my patients to climb stairs or hills as an exercise. Once the knee wears out, it can’t be recovered! Stair climbing or mountain climbing is a weight-bearing exercise, and the joints below the waist have to bear the weight of one’s body, especially the knees are under the most stress. When the body climbs up the stairs, the weight on the knees will instantly increase to about four times the normal weight. Take a person weighing 60 kg as an example: when walking on a flat road, the knees on each side will bear 60 kg of weight. When climbing stairs or hills, the weight on the knees instantly becomes 240 kg, equivalent to carrying a piano on each knee. Moreover, the faster the speed, the greater the pressure on the knee. Weight is the biggest enemy of the knee joint. Arthritis doctors said: climbing stairs or hills, the knee in addition to increased weight, but also to move back and forth, lateral twisting, especially the front of the knee joint patella area under the most pressure, the meniscus and other joint soft tissue will also cause wear and tear. Not suitable for climbing stairs, climbing people: 1, pregnant women or overweight people: any extra weight on the knee is doubly burdensome. 2, people with degenerative osteoarthritis: the soft tissues of the knee are already excessively worn, and continued improper use will aggravate the symptoms. 3, people with patellar ectropion problems: patella is inherently unstable, often climbing stairs or hills will make the ectropion problem more serious. 4, O-legged people: more wear and tear on the inner knee, excessive stair climbing or mountain climbing, will accelerate the wear and tear of the soft tissues on the inside of the knee, degeneration, making O-legged symptoms more obvious. 5, people with cardiovascular disease: climbing stairs or climbing, the heart’s demand for oxygen will increase, if not enough oxygen at once, may lead to myocardial infarction, if not timely medical treatment, and may even die suddenly. 6, more than 40 years old: because of the function of various parts of the body is gradually poor, should be less climbing stairs or climbing, stepping in place are better than climbing stairs or climbing.