I've been working out on an empty stomach for about 3 months now.. Other than the fact that I am totally drained of energy by the time I finish my workout and sometimes have trouble finishing the last reps, I still am able to complete them. Today was a great workout.. Chest, Back, Shoulders, Biceps, and Triceps.. Well I usually don't feel the soreness until tomorrow so I can't really say it was a good workout. AnYways I think it's fine to workout on an empty stomach imo. I usually have some Whey Protein an hour later... Just my two cents bye.