Marathon Training – The Fasted Run

Why would you need a fasted run? For you marathon running veterans out there, you will be more than aware that your body is capable of storing only a limited amount of glycogen – put simply, we have a limited carb store. Hitting the wall may seem like rite of passage, but it is not a situation anyone who has been there would like to be in again. In fact, for us non-elite runners, our body’s ability to store glycogen and to burn fat efficiently, and thus produce a steady source of energy, are the two biggest limiters of marathon performance. Elite runners need worry less because they are not running for long enough (I know! Not fair!).

How do we improve this? Well, one effective way is to do ‘fasted run’ training. Fasted runs are exactly what the name suggests – runs completed in a fasted state. Every couple of weeks, first thing in the morning, try an hour at an easy pace without eating anything before or during. Do not try anything too hard or long. Get out of bed, have a drink of water, and off you go. Your body will undergo various adaptation after a time that will allow you to store more glycogen, and break down fats more efficiently and also break down fats earlier on in the run before your carb stores are empty. Gradually increase the time you can run in a fasted state. These runs should not be hard and should be in addition to your main long run of the week.

You won’t feel as spritely as you normally do, but may well thank yourself from mile 20 in the race!