A Taoist has a will to preserve his body by maintaining a state of homeostasis. A normal body can handle the daily chores with no difficulty. Unless, there is an event which requires a quick response in all the sudden. Hence, the body must be prepared to handle any unexpected adverse situations. It is important to maintain the body in a state of balance, physically and biologically, at all times. Physically, it is the muscles of the arms and legs and other parts of the body for the freedom of movements. Also the arms and legs must have the strength to handle strenuous tasks. Biologically, it is the internal organs must be functional and fine tuned at their peaks.

The body needs to eat and breathe in order to have physical strength. A body can live longer without food than breathing. The ancients learned from this simple fact and see that breathing is very important for a living body. A Taoist knew that he must blend in and unite with nature by absorbing the chi of the five grains(五穀之氣) and chi of heaven and earth(天地之氣) to live. What does chi mean in these two terms? Before assuming it means 'energy,' let's interpret the character chi(氣) in these two ancient terms to make some sense out of it.

1. 五穀之氣(chi of five grains) : nutrient of the five grains; essence of the five grains; cream of crop.
It would be improper to interpret 氣(chi), here, as the "energy of the five grains" because the grains only have nutritional value. The benefit from the grains, 氣(chi) can be said to be the "nutrient of the five grains" or "essence of the five grains " or "cream of the crop" which provide nourishment for the body. It can be assumed it is a source of energy rather than an energy itself.

2. 天地之氣(chi of heaven and earth): essence of heaven and earth; air from heaven and earth.
氣(chi) in this term cannot be interpret as energy neither because there was no indication of what it is. Maybe the answer can be found in Heaven and Earth. It is very obvious that there are space and air in between Heaven and Earth. Since humans are breathing air in between Heaven and Earth, then, what else can they be absorbing besides sunlight.

Based on the above interpretation of the ancient philosophy, the body needs the chi's in terms of nutrients and air in order to have physical strength. In modern science, the biochemical energy generated by the body cells is adenosine triphosphate(ATP). The production of ATP requires glucose and oxygen for the body to function biologically and physically. The glucose is from eating and oxygen is from breathing.

Coincidentally, the ancient concept is analogous to modern science. In conclusion, the chi of the five grains is a source for the glucose and the chi of Heaven and Earth is the oxygen from breathing. The glucose and oxygen are the sources of energy for manufacturing ATP by the body cells. Hence, eating and breathing will enhance the functional activities of the internal organs.

Two and a half centuries ago, the ancients knew nothing about the manufacture of ATP by the body cells; nor they knew that there are oxygen in the air. However, the only thing they knew was that by breathing more air will improve their health. Therefore, the ultimate method of breathing was developed and cultivated for centuries known as Isometric Chi Kung or Static Chi Kung. For physical fitness, while practice breathing with slow movements causing the muscles to contract slightly, it will help to increase muscle tone, body strength and coordination. It was known as Isotonic Chi Kung or Dynamic Chi Kung.

If you are interested, do this exercise will help you to prevent hypertension.
http://www.youtube.com/watch?v=iguwo9rFBOs&feature=channel_page

Please see the result of the body coordination from practicing the above exercise for only 3.5 minutes.
http://www.youtube.com/watch?v=AKqttj_rV9g&feature=mfu_in_order&list=UL

Author's Bio: 

James S. Lee is a retired engineer and a practitioner of Tai Chi and Chi Kung for more than thirty years. Since Chi Kung has a great effect on the human body, he is searching for a possible scientific explanation of Chi Kung with Western science. He feels that the old Chinese concept about Chi Kung is very ambiguous. Therefore, there must be another way to explain it for a better understanding. Email: jlee1680@aol.com