Earlier quoted context omitted.
It's also a myth that runners need a high carb diet. I was a competitive distance runner for many years with a high carb diet and I'm confident that my performance suffered because of it. You're cells become much more efficient at using energy as you train, so you really don't need to eat that many calories at all. I was running 80+ miles per week, with a not above average calorie intake (for Americans), and my weigh…
The average American probably eats 60-70% carbs. They would do well on more like 25% carbs aka Paleo. As a distance runner, I don't perform well at 25% carbs. I need more like 40% carbs. So not "high carb", but "higher carb then a sedentary person needs".
Edit: Where "paleo" is defined roughly as "eating only foods that [I think] were available ~10,000 years ago": http://www.abc.net.au/science/articles/2013/09/10/3842158.ht...