Yi means "to change, to replace, or to alter," Jin means "muscles and tendons," and Jing means "classic or bible." Therefore, it is commonly translated as "Muscle Changing Classic, .... Tendon Changing Classic," or "Muscle/Tendon Changing Classic." "Muscles and tendons" does not refer only to the literal muscles and tendons. It actually refers to all of the physical system which is related to the muscles and tendons, including the internal organs. The Yi Jin Jing describes Qigong theory and training methods which are able to improve your physical body, and change it from weak to strong. Naturally, these methods are also very effective in maintaining your physical health.
The main purpose of Yi Jin Jing training is to change the physical body from weak to strong and from sick to healthy. In order to reach this goal, the physical body must be stimulated and exercised, and the Qi in the energy body must be regulated. The main goals of the training are:
1. To open up the Qi channels and maintain the appropriate level of smooth Qi circulation in the twelve primary Qi channels. This maintains the health and proper functioning of the related organs. Smooth Qi circulation also makes it possible to greatly strengthen the physical body.
2. To fill up the Qi in the two main Qi reservoirs—the Conception and Governing Vessels (Ren Mai and Du Mai, ). The Conception Vessel is responsible for regulating the six Yin channels, while the Governing Vessel governs the six Yang channels. When an abundant supply of Qi is stored in these two vessels, the twelve primary channels can be regulated effectively.
3. To open the small Qi branches from the primary channels to the surface of the skin and maintain healthy conditions for the muscles and skin.
4. For those who also wish to train Xi Sui Jing and reach a higher level, Yi Jin Jing is the fundamental training to build up the necessary level of Qi.