I'm pretty sure the rules say you can only have water.
you can have sports drinks as long as they aren't opened (or seal broken) before the bout and the commission approves. The real reason, and I'm not trying to be funny either, is after a while you keep drinking that stuff and you get hit in the stomach with a viscous body punch your pretty much fvkked. I know first hand that drinking anything other than water and getting hit in the stomach is the worst thing that can happen to you when competing in a sport.
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