How much you eat depends on how much you burn, i.e. how heavy you are and how high an effort you can sustain for that time. That said, anywhere between 125 and 250 cal/hour is the usual rando diet. The main thing IMO is to eat when you start to feel a little hungry. I don't go for the eat before you're hungry thing. That's a good way to overload your gut and do the technicolor yawn. I never eat a meal, mostly stuff from my jersey pockets and quick to eat stuff from convenience stores. I always have several hundred calories on me. I dribble the carbs in, a little at a time, but steadily. That said, the rando rule is that if you're feeling bad, discouraged, unhappy, whatever like that, you need to eat. That's the first thing you do. Worry about the rest later.
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