thats no doubt. i support zepp's take however if someone takes in slow releasing carbohydrate source and hour to 1.5 hours before working out, followed by a glucose dominated, right before the workout, that individual will have sufficient energy source to get through their workout, as long as that person isnt a fool and workout for 3 + hours. My pre workout meal consist of slower absorption protein and slow releasing energy from carbs about 1-2 hours before working out. (eggs and flax bread perhaps). 15-30 before working out, down goes 25 grams of whey and about the same about of glucose (either dextrose or maltodextrin).