PowerGoat it's according to a person's capacity to burn glucose. How much muscle and intense activity. If you're doing a ton of glucose-burning exercise, then you are not eating excess glucose. And it's the excess glucose that's the problem.

For example imagine a 180 pound man does 2 hours of high intensity exercise on a heavy training day. Say 1200 calories. Of which, 60% from glucose and 40% from fat, so that's 800 calories of glucose needed, so 200 grams of CHO. I would imagine he wouldn't need as much CHO since he's fat adapted, but intense exercise is just plain sugar burning.

Those of us who do Primal Blueprint style exercise, such that we do such hard training only once or twice a week, can get all that glucose from the glycogen replaced a little every day. Not like we need that much every single day.