The cases differ depending on which side has the issue, the Body or the Ki. A different issue in one side can have a different impact on the other.Although, this does not only refer to negative issues but also positive issues and impacts.
Body -> KiEdit
The relation between Body and Ki gives the ability to change the Ki by changing the body.
- Final Step of Training: The Body and Ki relation is more visible by the martial arts training itself. There is a limit to the level of strength humans can achieve with their Ki amount and the Ki center in everyone is about the same. However, humans have discovered that by changing the body the Ki changes as well. With the final step of training people widen their blood stream which is the part of the body with the most Ki flowing in it. This results in the increase of the Ki amounts, in order to fill the empty space in the veins, and the increase of the size of the Ki-center, to hold the larger amounts of Ki, and, as a result, the increase of the individuals strength and potential.
Ki -> BodyEdit
The reversed relation is also possible. The Ki and body exist in a balance. This means that a strong Ki needs a strong body to hold it. If this balance is lost then the body will break down and result to health problems or even death.
- Yin Body Type: The Yin Body Type is an example of blocked flow of the Ki. There are Nine-Yins in total and the number of blocked Yins determines the name of the Yin Body Type. When some (one-to-nine) Yins are blocked the natural flow in the body is distorted or completely blocked. This affects the balance of the Simgichehon and the individual has health problems. The severity of the health problems is equivalent to the Number of blocked Yins. In addition, if not healed the person cannot control the Ki properly and thus is unable to use martial arts as well. In contrast, if healed then the individual becomes much stronger than the average person in terms of potential. The One Moon Divine Dan has been proven capable of unblocking the blocked Yins.
- Overhaul Rebirth (Hwan Gol Tal Tae): The increase of the amount of Ki can change the body. Excessive amounts of Ki in the body rearranges the physique and bone structures as well as the organs. Although this is a very rare phenomenon and is usually called a miracle.
Martial arts are closely related with the domain of Medicine as well and they are the starting point of the Science from the belief that humans can affect the body through the Ki.
Techniques for healing are also existent:
- Inner Energy Healing: The user transfers his/her own Ki to another person in order to enhance the healing of that person.
The existence of Ki extents even as far as the Science of Medicine. Clans and Schools focus on controlling the Ki for healing purposes. Others study it further to enhance other factors as well. The most notable are the One Moon School and the Blood & Bone School. Starting by researching the and experimenting on Ki to improve their strength in the Murim they managed to learn the medical uses of Ki as well.
- One Moon School: The greatest, at the moment, medical center belongs to the One Moon School. They have researched for many years on the ways of the Ki and have learned healing and treatment ways that are generally not known in the Murim. They are capable of treating a broken Ki-Center that was thought to be impossible and are capable to hold in comatose state a person that was shot in the head.
- Blood & Bone School: The Blood & Bone School focused on the use of Ki to permanently enhance certain functions of the Human body. Seung-Jae is the first and only example of this having enhance his vision to the point of reaching the level of night vision (Yah Myung Ah), although he lost his hair in the process and has now resorted to wearing a wig. In addition this school also has a history on pills related to Ki. Also, Seung-Jae was able to make a cure for the Nine Yin Body which was said to be incurable hinting that the school managed to find a cure.
- Mil-Yang Clan: Although not an especially long history with medicine the Mil-Yang Clan has shown skill in medicine by creating an improved version of the Ma-Hwan Dan, the Jin-Gi Dan.
- Heung-In Hospital: The Heung-In Hospital specialize in Ki healing. Currently their head, Ju Sang-Sik is treating Kang-Sung, who suffered critical internal injury after his fight with the Nine Arts Dragon. Also, the good doctor manage to heal Shi-Woon's mother who was in comatose state and other doctors were not sure she could wake up.
- Main article: Spirit Medicine (Dan)
The Medical Sciences even reached as far as the physical form of pills that had a direct effect on the Ki. These pills were named Spirit Medicines since based on the Simgichehon the Ki is the Spirit of the body. Each pill has different use and different effects and side-effects. Their use is not limited to the health issues but extends to the human desire for power. Known medicines are:
- Il-Wol Sin-Dan (One Moon Divine Medicine)
- Hwan Dan (Circulation Medicine)
- Ma-Hwan Dan (Evil-Circulation Medicine)
- Jin-Gi Dan (Accelerating-Ki Medicine)
- Bo-Hyul Dan (Blood Supplement Medicine)