This period lasts from 5pm to 7pm where the kidney channels take the lead. The kidney system (channel) is the main storage of essential vital energy "Jing". What is vital energy "Jing"? To human beings, vital energy "Jing" is just like saving money in the pocket, and buys anything you need. If any problem occurs in the structure of cells, this kidney vital energy "Jing" will "liquidate" or help recreate the cells. Vital energy (in the kidney) is the most "creative" essential power in human body. When one's energy is nourished and regulated, the energy will be able to help recreate anything that the body naturally requires. For example, if there is a lack of red blood cells in the body, this vital energy will help to "liquidate" red blood cells to meet the lack of it.

From another point of view, since vitality "Jing" is stored in the kidney, vitality is already inherent in our bodies, which is the phrase, a breath of life", or "as long as there is a breath left in me…" This is also why when Chinese people reach to a certain age in life, they would start going into details about nourishing the kidney system, and each body has its own natural regulated flowing system; if the kidney channel cannot flow normally, the vital energy will not "liquidate" to support the body no matter how much nourishments one takes; nourishing the kidney vital channel depend on how strong one's digestion system is.

According to TCM philosophy, well-nourished kidney energy could tell how strong one's ambitions are. For instance, an older person usually does not have high or deep ambitions for a new and tough business due to their aged kidney system (low vital energy); however, a young person with a stronger kidney system (high vital energy), will have high, or deep ambitions for a tough and new business. Therefore, if one wants to accomplish big endeavors in life, one has to start with protecting and nourishing the kidney system, which means to build a better vital energy in your body.

Please be advised that to build a better vital energy cannot rely on any Viagra, but rely on one's daily food, Viagra can do nothing to your internal energy but to
overdraw your vital energy. That is why TCM philosophy always suggests the youth to hold "Jing" for your life, in other words, not to make excessive love in your life so as to live longer.