The way our body is constructed is to contain an energy system of meridians, other than the known systems such as the lymphatic system, nervous system, etc. Those meridians are channels not unlike blood vessels, but with energy flowing through instead of blood. They affect the body and the substance exchange in it.
This Chinese biological clock can show us the intervals in which energy circulates through the body, and the strongest energy levels in an area of the body every two hours. If there are problems in that particular area, the symptoms are noticeable.