As you breathe in & out, you move the energy ball to different points (navel, heart, ...) and push it down to your toes. You do everything without adding the movement of your legs. That is a simplified version.
Of course, if you want to lift up your leg as you bring the energy ball up, and push your heel down to earth as you push the energy ball down is perfectly okay. It was simplified by Master Jim as lots of people have problems with this movement.
