Glycogen reserves are soon used up — just about the time during your run when you notice the exercise is suddenly much harder work. That is why nutritional physiologists say we should do at least an hour’s exercise if we want to burn fat. It is not until we pass through that first energy dip that we start to tap into those fine reserves. We might find it annoying that our paunch isn’t the first to go, but our body is deaf to such complaints. The simple reason for this is that human cells adore fat.
