|（Academy of Mathematics & System Science，Chinese Academy of Sciences，Beijing 100190，China）
Abstract: Exercising and appropriate exercising are two different concepts. Ill effects of inappropriate exercising are not caused by exercising. Unscientific exercising ways would damage key areas of the body of the exerciser, being the main cause for sudden death in exercising. By analyzing the sudden death of a fan of Hyman, ZHU Gang and Cooper as well as 3 cases of sudden death in Beijing International Marathon, the author concluded that these tragedies could be avoided. The “natural life span” theory and Hyflick's theory failed to correctly describe the aging and life limit of human beings; there is no factual ground for the presumption of “exercising increasing body tem-perature thus shortening life span”; “human body freezing will prolong life span” is only a preliminary hypothesis but not reality, all these conclusions can not be used in scientific demonstration. Touching stories of WANG Jia-peng, PENG Shui-lin and Cancer Fighting Paradise at Beijing Yuyuantan Park have shown important contribu-tions made by rehabilitation exercising to the society. The deer and wolf story of HONG Zhao-guang is provided with educational meaning from the perspective of survival environment.
Key words: fitness exercise；sudden death in exercising；long life；rehabilitation exercising；PAN Chao-xi