i'm not sure I understand, what muscle are you referring to?
what I mean is, I don't see any weight lifting in the workout, unless this is a new workout plan to attempt to lose fat (and muscle with it)..
you can't really expect to have muscles if you don't work them, and overworking cardio has a possibility of putting your body into a catabolic effect, does it not? I don't believe that ephedra/
caffeine would help you at all to retain any sort of muscle, but maybe something like
glutamine? Or maybe check into some
avant labs products (i only mention them because i visit their boards so often, and people seem to be pleased).