I can't tell you how long you will need to stay on the keto ultimate diet, it will vary from person to person. However, after you think you have reached ketosis (the state where your body is burning fat as an energy source), you should be ready to re-introduce small amounts of complex carbohydrates (raw oatmeal) back into your body to help you through workouts. If you are going to be training, and especially training hard, you will need some form of carbohydrates.
