I am currently doing the fat fast and I'm doing well. However I had a question. I read on this low-carb site that you should not exercise while on the fat fast because it's only 1000 calories. They said it will cause a calorie deficit. I just wonder how that would be so with all the fat one has to burn... wouldn't you just burn fat? And if thats true and if eating less than 10-12times your weight in calories causes your body to go into starvation mode, then why does the fat fast work?