And why not? though the elite will have far more sophisticated plans
'Do not change your normal diet drastically in the last week before the marathon, but decrease your intake of protein (meat) and increase your intake of carbohydrate (pasta, bread, potatoes, cereals, rice and sweet things), especially for the last three days when you should also be markedly reducing your training. This loads the muscle with glycogen. Unless you reduce your protein intake you will not eat enough carbohydrate. (Not all runners are helped by first depleting carbohydrate with a long run and low carbo diet and then loading — this can make your muscles very heavy.) '
'official' London Marathon advice.
I eat some extra carbs the day before a marathon, though far more during the very high mileage training weeks (I also take less insulin in those weeks, because my insulin sensitivity becomes very high) . I drip feed carbs during the marathon and normally manage to complete it with no hypos (ie I don't hit the wall) and a BG level between 4 and 6. I'm slow and out for at least five hours so I need to be well fueled. It might not work for you but it works for me.
