I did that once got pretty nauseas. I did am cardio religiously last year and i Think i ate up alot of muscle got down to like 175 @ 7% From 190 @ 10%, I did did afternoon/evening cardio and got from 195 @ 10% down to 190@ at 7%, my opinion it sucks, coupled with the fact you get less sleep because you wake up earlier, your cortisol levels shoot through the roof, your testosterone goes down, it plain sucks. Bodybuilders, make it a point to eat every 3 hours, to prevent catabolism, and thats pretty much what your doing in the morning. Youll definately loose more weight, but its like 1:1 fat:muscle IMO.