Is it good for life? Or does it hurt? The New England Journal of Medicine study points out: climbing stairs can prolong life, each step, live 4 seconds longer. However, we often see people struggling on the stairs, knee pain to go upstairs, and even the more climbing knee problems more serious. So, climbing stairs or hills, in the end is not a good exercise? Experts say: stair climbing or mountain climbing, indeed, has many advantages such as enhancing cardiopulmonary function, calorie consumption, but the disadvantages are so serious that it really is not worth the loss. Therefore, in her 30 years of medical practice, she has never advised her patients to climb stairs or hills as exercise. Once the knee wears out, there is no recovery! Stair climbing or mountain climbing is a weight-bearing exercise, the joints below the waist have to bear the weight of their own bodies, 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. Orthopedic surgeons say: when climbing stairs or hills, in addition to the increased weight on the knee, but also back and forth movement, 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.