Final answer:
For exercise lasting over 2 hours, the carbohydrate intake recommendation is 3-10 g/kg/day depending on exercise intensity. Carbohydrate loading with complex carbohydrates is advised to ensure a steady energy source. Hydration remains essential alongside carbohydrate intake.
Step-by-step explanation:
The recommendation for carbohydrate consumption for exercise lasting over 2 hours is to increase intake from about 3 to 10 grams of carbohydrates per kilogram of body weight per day, depending on the type and intensity of the exercise.
For endurance athletes, like marathon runners, carbohydrate loading is a common practice to maximize glycogen stores in muscles and the liver.
A significant part of this should come from complex carbohydrates, such as bread, pasta, and potatoes, because they are broken down more slowly and thus provide a steadier source of energy during prolonged activities.
It is important to note that while the American Heart Association recommends about 55% of your daily calorie intake to come from carbohydrates, these should be mostly from complex carbohydrates and not from simple sugars found in candy and junk food.
Also, remember that proper hydration is crucial during long periods of exercise to maintain optimal performance.