Did you try to stop the movement in your body and observe what happens?
There is still some movement, everytime that i breathe in, my lungs expands, my chest opens and even my belly is touced by that air.
It is not posible to stop that movement it is like to stop life, but this body stillness can help us to FOCUS our attention in some specific parts of our body.
We (most of us living in occident)since we have been born we are used and trained to direct our attention to the outer world, outer world like outside our bodies.
What happens when we start directing our attention to our inner world?
You can try now, take a comfortable sit, set your alarm clock 3 min, stop your body and start….don´t muve until the alarm clock rings, what do you observe?
How much can you stop your body? How much can you stay observing the movement of your body happening anyway? How long can you keep you mind vague, without a focus, just in the state of attention?