I've just began a new diet based on the carb cycling approach. Little background: 6'2 200lbs around 11-12% and train with high (cardio)intensity, boxing oriented workouts. Weights are still in the picture, but take a backseat to bagwork, shadowboxing, sparring, etc. I'm basically trying to keep/gain strength, while shedding all possible fat and get into top shape cardio-wise. To the point, I'm about 2 weeks in on a carb cycling diet, and on the day after my NO carb day, I have ZERO energy. Now, I was under the assumption that fat would provide a sufficient, if not better source of energy to replace the lack of carbs. I've heard this can be just a temporary deal from your body getting used to the lack of carbs, but the lethargic effects are very detrimental to my workouts. So, in your opinions, will the body usually get used to burning fats for sufficient energy, and this carb withdrawl type ordeal pass? Or are carbs absolutely essential for the type of goals I've set? Thanks