It is common to have blockages in the body, these blockages can cause pain and many disruptions in the body, in short where there are blockages, caused by injury, stress, tension, injury, etc. the body has to work harder in order to get back to homeostasis, in working harder it deprives the body of a free flowing experience, for eg. If you eat too much, your body will move all its energy to the digestive system to break down the food, store what is needed and get rid of the rest, this will leave you tired and lethargic and in this state you are not very productive and you can lack focus and ambition.
This example came form a diet perspective, the same is true for tension and stress in the body, this effects your overall circulation and the body is in a constant fight to get back to a neutral state, with the correct amounts of relaxation and tension.
Where there is less tension and stress there is a more intense sense wellbeing.
Shiatsu works to diagnose the individual whilst treating and balancing the excesses and insufficiencies in the body that are creating this sense of tiredness.