How low is ur carbs intake. Carbs are ur body's preferred fuel source- ur muscles, brain and other tissues rely heavily on a continued supply of carbs to satisfy immediate and long-term energy demands. During resistance training, the body relies mostly on carbs for fuel, and the amount u have stored in ur body will affect ur stamina and endurance. Bodybuilder's daily carb intake should consist of 2-3 grams per pound of bodyweight, about 50-60% of total daily cals (Muscle & Fitness, Feb03). Bottom line if ur not getting enough carbs u can place ur muscle gains, metabolism and energy at risk.