Consuming sugar during long endurance events can commit the body to a pure glycolytic strategy with a risk of energy crashes.

“you have now committed to a pure glycolytic strategy and you better have it timed perfect you and it is part of the strategy and you know and argue in terms of optimizing performance should be part of your strategy but you you only get one shot at it so if you're doing a hundred you better you know if it comes before my lady you better know what you're doing because after that I'll be know if you're gonna take a mountain Dew don't do it at Mile 20 because it is at that point all bets are off your body is now shifted into a completely different world and it's gonna want to stay in that world and you know that well”