I found this interesting article about a recent study that compared sports drink to a placebo and then did MRI on participants. What they found was pretty interesting.
Basically the brain/body recognizes glucose or maltodextrin and then reacts by increasing endurance. Read the article by clicking the link below. The interesting thing was that the cyclists did not swallow they simply swished it around in their mouths for 10sec.
I guess I can go with the small size now. lol.