Race Day Nutrition
It is very easy to get carried away with 'special' sports drinks or supplements that are going to help you perform at your best on the day of your race.
However, in reality the most important things to do are to make sure you have enough glycogen and fluid on board.
This is done in a similar way to your intake of food and drink before a training session, but it is likely to be a little earlier before your the race as you are going to be working as hard as you possibly can (not always true for training sessions).
One very important thing to note is the time of day that you are racing - if you are running in the morning, you should practice preparing your body for that time of day. Even if you are not going to be doing training sessions at this time of day (though doing this every now and again would be ideal), you can still make sure your body is happy with your eating early. For example if you are doing a race at 9.30, you will probably want to have eaten by 7.00am at the latest. It is vital that you do eat on the day of the race, but doing so too late will only make you under-perform.
This should follow the same sort of regime as for training, trying to get fluid along with a bit of sugar and protein consumed as soon as you feel like it and then having a full meal with two hours. It is easy to not do this as diligently as when training as you may be thinking about the race, talking to friends or having a post-race celebration - but it is worth considering that the recovery from your hardest effort of all your running (or at least a race should be) should really have the best plan for recovery as well.
There is often a lot of talk about marathon carb-loading. To an extent this is a bit of a myth as you don't need to eat as much extra food before the race as you might think. Running a marathon will use about 3,000 calories for an average-sized person. This is a lot, but it is not unusual for athletes to load up so much that they will consume up to 10,000 extra calories in a week when they are doing much less activity than normal.
This will just leave you feeling bloated and heavy as you race - the total opposite of what you might be hoping for.
In fact, it is not unusual for athletes to use fewer calories in the week of a marathon, despite the race, because of the light workload in the final few days.
We suggest you make sure you have a good meal, high in carbohydrates, the day before your race, but don't overdo it.
During races it is a good idea to take on fluid (small amounts every 20 minutes or so) and ideally some carbohydrates, whether this be sports bars, drinks or even jelly beans.
The information here is written by athletics coaches who have read widely into the subject and not a sports nutritionist, so is about gearing your food and drink to the practicalities of running.