There’s a book called Impro by Keith Johnstone.

It’s a book about improvisation, though in there there’s a very interesting part on moving your center around when it comes to character work.

So long as the centre remains in the middle of your chest (pretend it’s a few inches deep), you will feel that you are still yourself and in full command, only more energetically and harmoniously so, with your body approaching an “ideal type”.

As soon as you try to shift the centre to some other place within or outside your body, you will feel that your whole psychological and physical attitude will change, just as it changes when you step into an imaginary body.

You will notice that the centre is able to draw and concentrate your whole being into one spot from which your activity emanates and radiates.

(Johnstone, 1987, p. 179).