What risks result from carbohydrate loading?

Useful, but also....: Useful only in sports requiring brief spurts of energy. Forming glycogen stored in muscle or liver is the scientific goal. But carbo loading is rendered useless after twenty minutes of vigorous activity, when the major enjory source is free fatty acids, not carbs. For more endurance activities, carb loading is scientifically antiquated. So, playing football, ok. Mountain biking, running, no!