"Long-distance athletes such as marathon runners often go into glycogen debt, where almost all of the athlete's glycogen stores are depleted after long periods of exertion without enough energy consumption. This phenomenon is referred to as "Hitting the Wall". In marathon runners, it normally happens around the 20-mile (32 km) point of a marathon, depending on the size of the runner and the race course. However, it can be delayed by a carb loading before the task.
When experiencing glycogen debt, athletes often experience extreme fatigue to the point that it is difficult to move."
Quote from Wiki...
Basically the general consensus is to taper plus carb load so that the glycogen stores are full prior to the event.
However it has also been suggested that by going long, the body gets more economic in using glycogen so that the Wall is pushed beyond 26 miles.
So all you who have recently completed a marathon and have rested and eat well will be in a good position.
