Many people practice tai chi, chi gong, and so on with the aim of keeping their bodies fit for a long time. There is certainly nothing wrong with keeping one's body fit-indeed, it is one of the aims of yoga-but unfortunately, many such people are trying to run away from the inevitable death of the body. Some mystic yogis strive to keep their bodies alive forever-but that is not possible. Even if one was the greatest yogi and could keep his body alive for thousands of years, that still is not forever.Jagad Guru Chris Butler - Science of Identity Foundation