I think it is hard to apply that level of precision between the positions. When they have the ball that may be true of the backs, but most of their high intensity runs are done without the ball, in support, constantly adjusting their lines. Likewise, are we differentiating between the outside backs, or the scrum halves, who would usually be stepping, cutting or swerving and then running? I would just keep it as simple as make sure you’re doing some running, make sure you’re doing some changing of direction and some getting up and down, then the rest is up to you. Feel free to play with the concept as you like.