Shiatsu is based on the idea that we have a subtle flow of electro magnetic energy flowing around our bodies. This can be photographed using a process called Kirilian photography. There is also scientific evidence to show that cells pass a subtle charge of electromagnetic energy from one to another.
In humans this energy, called chi in China or Ki in Japan, is highly influenced by our emotions. We feed our cells with our emotions through this flow of emotional energy. Chi tends to flow along major pathways, called meridians, before spreading out into smaller passages reaching every cell. Along these meridians are points, tsubos, where the flow of chi can be changed more easily. A shiatsu practitioner will seek to improve the chi flow in a way that resolves physical problems and help a person feel better.