Before race day it is important to practice pre-race nutrition, having a clear plan in your mind what you can eat before, during and after the event.
Pre-race meals should include enough calories to provide fuel to get you round and should be practiced in training beforehand. Many runners often like a calorie hit the night before such as a slice of cake, think of it as extra fuel for the fire!
Check out event websites to see what drinks or gels are offered during the event and experiment in training beforehand so that you adjust your intake to suit your needs.
A mistake runners often make is failing to refuel after the event has finished. Many races provide goodie bags, which often contain post-race snacks, ideal for getting something in during the 20-minute window.
Failing that, look for foods high in carbohydrate and protein to optimise your recovery and remember to hydrate well, even after you've crossed the finish line.