Everybody receives their original essence from the union of their mother's ova with their father's sperm cell. This is called the original essence - Yuan Jing. The amount of Yuan Jing in each person varies. To sustain our life and enhance it, we must conserve our original Jing.
The amount of our original Jing determines our original Chi. We can see that the original energy carries us and sustains us throughout our lives, from the moment we are born to the time of our death. Many of the Chi - Kung practices are designed to restore the free flow of energy throughout our body's channels!