Reading the excellent book Exercise Endocrinology got me thinking about what would happen if we would train during the final hours of a fast and delaying the post workout meal as long as possible. Some background info: Both fasting and exercise are catabolic. Fasting will make insulin levels to drop and GH and cathecolamine levels rises when glucose levels drop, which will promote lipolysis, but gluconeogenesis is also promoted which would lead to loss of muscle protein. A dilemma. The real increase in lipolysis doesn't occur until after the the bout, at the same time as GH levels are the highest. This would lead to greater fat burning post workout. But, if we eat carbohydrates or protein an insulin rise would inhibit lipolysis and would stimulate storage of glucose and stimulate both glycolysis and oxidation of glucose while sparig muscle protein. The questions: 1) How much loss of protein would we see per time unit? Any studies on this? 2) How much of a delay before eating a post workout meal is feasible if we want to time the meal to benefit from the increase of PS (insulin will also stimulate PS)?