Regarding an exercise from Micheal Chekhov...

In To the Actor by Michael Chekhov, there is this exercise in which I have to imagine that my flow of energy is coming from the centre and that my energy has to be streaming from the centre to each of my limbs (this is exercise 2 btw). I've been wondering is it normal to feel some kind of "ache" in your limbs when doing this exercise?

Also, when doing this exercise, there is this passage here that I don't understand how to go on about it; "Let the power which flows from the imaginary center within your chest and leads you through space precede the movement itself; that is, first send out the impulse for the movement, and then, an instant later, do the movement itself." Do I have to pause every time I make a movement to imagine it coming from my chest? If not, how exactly do I do this exercise properly? Also to clarify, I have only been doing this exercise for two days but it's hard when I do not have a teacher to correct me when doing this exercise.