While training, make sure to eat something every 60 minutes. The body only has 90–120 minutes of stored energy; after that, the dreaded "bonk" quickly follows. "Bonking" feels terrible and also has implications for the next workout, because your body is completely drained of its energy reserves. It is far better to provide fuel for the body when it's needed — while training — rather than trying to play catch-up after the fact. To avoid running out of fuel, which makes recovery and the next workout more difficult, eat 50–80 grams of carbohydrates every hour during exercise greater than 1 hour in duration. For exercise lasting less than 1 hour, simply staying hydrated is the most important thing.