True essence in the body is like the sap in wood
Yuan Huang 16th century CE
Our own personal constitution is something with inherent from our parents and them in turn from their parents. If we carefully observe others around us we can see how different we are in comparison, how we have a tendency for different types of illness and weaknesses, how some catch colds and viruses more frequent while the more robust of us are seemingly never ill at all. Of course people’s lifestyle makes a tremendous impact on wether people are healthy or not but it is likely a persons constitutional strength plays a big role.
The ancient Chinese call this constitutional strength jing which translates into English as essence. We have two kinds of essence or jing, the first is ‘pre heaven’ which is the one we are concerned with in this discussion and ‘post heaven’ which is refined by our own hand, the food we eat, our environment in which we live and amount of the right exercise we do.
Traditional Chinese Medicine describes the ageing process as a decline in this essence (jing). The kidneys have been given the job of storing this essence in which is also said to effect our bones, brain, teeth, and fertility. So as we age and our essence diminishes so does naturally everything else that is associated with it.
The way to preserve Jing is by striving for balance in all life’s activities. Balance meaning moderation in diet, work/rest, sexual activity. Irregularity or excess in these areas wastes Jing and can never be gotten back. Certain exercises can also help to persevere Jing, such as breathing exercises, Taiji (Tai Chi), and Qi Gong.