Qi, blood and body fluid are the basic substances of the human body, and are the basis of all its physiologic activities. Qi is a kind of energy , flowing around the whole body to maintain its life activities, while blood and body fluid are the nourishing and moistening substances, circulating in every corner of our body. It is really important to note that qi belongs to yang while blood and body fluid belong to yin.

Qi

The Concept of Qi

Qi is the virtual substance, and its concept is based on the ancient Chinese understanding of natural phenomena. It is thought to be the most basic substance of the world. Both everything and every phenomenon in the universe result from the movements and changes of qi. In the human body, qi is the vital substance constituting it, and maintaining its life activities. Qi is able to go around all the body. The routes through which qi goes, are called the channels that connect acupunctural points to be explained later.

The Function of Qi

1. Promoting function : Qi promotes the growth of the human body by activating the physiological functions of organs and tissues, and by helping the production and circulation of both blood and fluid. The deficiency of qi causes the retardation of the growth, hypofunction of organs, the insufficiency and stagnation of blood and fluid, leading to a variety of symptoms such as general fatigue, anemia, loss of appetite, diarrhea etc.

2. Warming function : Qi keeps our body temperature on a constant level by its warming action. This is why the deficiency of qi results in hypothermy, cold limbs syndrome etc.

3. Defending function : Qi defends our body on the surface from external pathogens like virus and bacteria. It means external pathogen can not easily invade our body if qi works well. So we could say qi has a kind of the immune function. People with weakened qi are susceptible to common cold, pneumonia and other infections.

4.Transformative function : It means all the function concerning to the metabolism and the transformation of qi, blood and fluid.

5. Containing function : Qi prevents the extravasation of blood by controlling it, excessive loss of body fluid by adjusting the secretion of sweat as well as the excretion of urine. In addition, Qi consolidates organs to prevent them from drooping below their normal positions.

The Formation of Qi

Qi has two different sources : one is "vital substance" inherited from parents, the other is food, water and air. The vital substance is stored in the KHS (Kidney and Hormonal System) after inherited from parents. It is called "essential qi".

Fresh air is transformed into "cosmic qi" after inhaled into the LIS (Lung and Immune System), while food and water are converted into "digestate qi" by the DAS (Digestive and Absorptive System). Both of qi's are then combined with each other, to become "ancestral qi". Finally the ancestral qi is combined with "vital substance". This is "original qi", the basic form of qi.

The Classification of Qi

Original Qi

The basic form of qi is "original qi", which is the most important of all. "The original qi" circulates throughout the whole body, activating and promoting
its vital activities.

Ancestral Qi

The qi gathering in the chest is called "ancestral qi". The functions of "ancestral qi" are as follows:

control the respiration ------ the strength of breathing and voice is related
with "the ancestral qi".

regulate the heart beat and blood circulation ------ heart beat and blood circulation as well as the temperature of the limbs depend upon "the ancestral qi".

Nourishing Qi ( Construction Qi )

The qi, circulating with blood through the vessels , is called "nourishing qi". It derives mainly from food essence, and its functions are as follows:

produce blood

nourish the entire body

Defending Qi

Defending qi flows outside the channels, and its functions are as follows:

defend our body surface to prevent the invasion of exopathogens

warm the organs

The Qi of Control System (Organ Qi)

Every control system has its own qi.

The qi of control system promotes and activates the physiological function.