16 and 17, Robert Burton, the author of the famous British writer The Anatomy of Melancholy, said: "Many people are keen on frequent and intense labor and sports. The most strenuous exercise must not exceed the limit of starting to sweat. Once crossed, it is dangerous. " Of course, the reason given at that time was not the theme that "human cells can only divide 50 times, and exercise and fitness can accelerate metabolism"

He said: "The great physical exertion caused by strenuous exercise can be felt in all parts of the body, but it is one of the most important pressures in the cardiovascular system." Long-term strenuous exercise can harm any organ of the body, especially the heart. Or "sports loss will not cause special losses in the short term, but the cumulative effect will bring problems to later life, leading to early death and shortened life."

The word "sports longevity" seems to have occupied the mainstream of academic circles until the beginning of the 20th century. Most of the evidence is people's impressions and anecdotes. For example, some athletes' strenuous exercise led to the rupture of aortic blood flow, and some athletes died suddenly on the sports field. This view has also led to many more rigorous studies. For example, the most interesting is the men's canoeing between 1860- 1890.

Cells can only divide 50 times. Does fitness speed up metabolism? Does exercise reduce people's life span? The result is among athletes, intellectuals and random controllers, and among other athletes. In other words, according to the intensity, there is not much difference between the average life expectancy and the cause of death among sports teams. This study was published in 1954 British Medical Journal. At the same time, the strict epidemiological investigation published in 1953 confirmed that,

Due to lack of exercise, life expectancy is obviously shortened, which affects the risk of smoking on the shoulders. Since then, a large number of studies have provided sufficient evidence that coronary heart disease, type 2 diabetes, breast cancer and colon cancer will greatly increase the risk of chronic diseases by 6% due to lack of exercise, reaching 10%. At the same time, 9% premature death is increased, which means that life expectancy is significantly reduced. What does a 9% increase in mortality mean?

Insufficient physical activity seems to bring considerable health risks to smoking and obesity. Therefore, eliminating unhealthy behaviors with insufficient physical activity, just like eliminating smoking and obesity, has the function of prolonging life.