CSSD Practice Exam 2026 – Complete Study Resource

In very high-intensity activities lasting 4-5 hours, the carbohydrate requirement is critically elevated to support endurance and prevent muscle glycogen depletion. The recommended intake of 8-12 grams per kilogram of body weight per day is grounded in the understanding that carbohydrates serve as the primary energy source during prolonged, strenuous exercise.

During such extended periods of high-intensity activity, muscle glycogen can be significantly depleted, necessitating a higher carbohydrate intake to replenish energy stores, maintain performance levels, and support recovery. This threshold also accommodates individual variations in energy expenditure and the specific demands of the activity.

The other intake ranges, while beneficial for different levels of activity, do not meet the energy demands of very high-intensity, prolonged efforts, thus underselling the amount of carbohydrates necessary to effectively fuel such extensive physical exertion.