(IV) Avoiding overstrain
Avoiding overstrain means avoiding too much mental and physical labor.
First, we should not overstrain our spirit. The over-excited, over-strong, and over-long emotions will strain the mind and spirit. “The heart is the master of all viscera. When the heart moves, all viscera will sway.” Once the mind gets overstrained, the blood and Qi in the viscera will be inevitably impaired. Therefore Yellow Emperor’s Classic of Internal Medicine says: “Anger impairs the liver, joy impairs the heart, worry impairs the spleen, sorrow impairs the lungs, and terror impairs the kidneys.”
Second, we should not be too laborious. Being laborious, i.e. long-time and excessive use of strength will cause physical discomfort, as Su Wen: Ju Tong Lun says: “overstrain consumes essence”. Su Wen: Xuan Ming Wu Qi Pian also says: “Excessive staring impairs blood, excessive sleep impairs Qi, excessive sitting impairs flesh, excessive standing impairs bones, and excessive walking impairs tendons”.
In addition, we should not overstrain our kidneys. In other words, we should be moderate with sex and do not get exhausted. “Do not have sex after drinking alcohol, as this will consume the essence and vital Qi due to addiction”. Su Wen: Sheng Qi Tong Tian Lun says: “having too much sex will impair the kidney Qi and the reproductive functions.”
(V) The key to health preservation is the maintenance of essence, Qi and spirit
Essence, Qi, and spirit are three treasures of the human body. They can be converted into each other and enhance each other, serving the metabolism of the human body.
Essence is the basic substance that constitutes the human body. It is divided into congenital essence and postnatal essence. The congenital essence is inherited from parents and mainly stored in the kidneys. The postnatal essence is the essence for the viscera. It originates from food and inhaled fresh air. After being converted by the spleen and stomach, it is delivered by the heart and lungs to all viscera and limbs of the body.
A part of the essence is delivered to the viscera and then consumed. The rest is stored in the form of “kidney essence” in order to nourish the congenital essence for a rainy day. When the human body is struck by a disease which consumes too much essence or the body is too old and weak to provide sufficient essence, the essence stored in the kidneys will be used for emergency. Once the disease is cured, some essence from the viscera will be delivered to the kidneys in order to make up for the deficit. If the disease is too serious and the functions of the organism are too low, the postnatal essence will no longer cover the deficit and the congenital essence will be consumed. Once the kidney essence is exhausted, the life will come to an end. Therefore most health-preserving masters, and especially those of the Taoist school lay great emphasis on the nourishment of essence.
The growing, strengthening, aging, and dying process of the human body, which is discussed in Su Wen: Shang Gu Tian Zhen Lun is exactly a process in which the kidney essence－ “Tiankui” turns from flourishing to declination. The process of health preservation is exactly a process of essence preservation. The finite essence is utilized to the greatest extent in order to achieve the “natural span of life” deserved by the human body.
Essence preservation is of extreme importance. We can only reduce the speed of consumption by regulating the mind and spirit and keeping away from overstrain and diseases. Postnatal essence can be replenished but we cannot directly inject it into the body. We can replenish it only by nourishing the spleen and stomach and constantly improving and maintaining the vigorous functions of the spleen and stomach, the foundation of acquired constitution. Even if we grow old, we can still maintain the active functions of the spleen and stomach and the efficient generation of nutrient Qi. The generation of nutrient Qi will nourish the viscera and provide material basis for the conversion of essence for the viscera. It is only in this way that the essence in the kidneys can be replenished. As long as the postnatal essence is sufficient, the congenital essence will be seldom used and therefore last for longer time.
The nourishment of Qi is also an important link. We can nourish Qi mainly by nourishing the spleen and stomach-the foundation for acquired constitution, the lungs-the location for the generation of initial Qi, and other viscera important for the transmission of blood and Qi inside the human body. In daily life, we should “eat and drink moderately” and must not drink too much alcohol, eat excessive food, eat too much delicious food, have diet preference, or eat dirty food. We should minimize the burden on our spleen and stomach in order to maintain their good operation. During the nourishment of Qi, we should also take good care of the lungs, i.e. the respiration. By regulating respiration, we can focus our mind, relax our body, and thus improve the effectiveness of Qi intake and facilitate the circulation of blood and Qi.
Another important aspect of health preservation is the nourishment of spirit. Spirit is stored in the heart, which is the grand master of all viscera. The nourishment of both Qi and essence has to be realized through the regulation of spirit. Yellow Emperor’s Classic of Internal Medicine says : "vitality indicates a favourable prognosis, and loss of vitality will lead to death." It is only through spirit regulation that we can keep all viscera to their due places. When the heart is calm, all viscera will be at ease. When the heart is troubled, all viscera will sway.
Therefore Yellow Emperor’s Classic of Internal Medicine lays great emphasis on the nourishment of essence, Qi, and spirit for health preservation. Essence, Qi, and spirit are all indispensable. Essence can be converted into Qi, Qi can be used to nourish spirit, and spirit can regulate the conversion between essence, Qi, and spirit.
(By Jian Liujun)