Hi, From personal experience, I found that it was crucial to train my stomach to be comfortable with eating specific foods 2 hours before the race. This ensures optimal performance and no G.I (gastrointestinal) problems. In terms of making sure we have enough energy and fuel on board, if a decent meal is eaten the night before, and a few hours before the race, the human body has enough energy for up to 80 minutes of endurance activity. This means “bonking”, or in other words, running out of glycogen stores for muscle recruitment is not so much of an issue for shorter races like a 5km or 10km. However, since you're running a marathon, it's important to incorporate in-race nutrition that has been tried and tested in training. Keep that in mind.
Breakfast
I like to stick with a mix of simple and complex carbohydrates. We want energy to be easily accessible and be enough to keep you satiated on the start line and throughout the race. For example, I generally eat oats, maple syrup/honey/brown rice syrup, and a banana 2-3 hours before the race. This is my go-to breakfast before some of my major 5 and 10km road races.
½-¾ cup of oats, cooked on the stovetop so they are well done. This decreases digestion time.
1 teaspoon of honey, or maple syrup (slightly more if using the latter option)
Chopped banana on top
Dash of cinnamon
Toast with banana and honey is also a very good option if you’re not a big fan of oats. I like to stick with white bread or sourdough the day of the race, rather than a grain bread or wholemeal/wholewheat, as this can cause stomach upsets.
What should I eat the night before ?
Remember for a marathon it's important that you've practiced and thought about your nutrition strategy. It's a good idea to use training to practice meals and see what works for you. A decent meal which includes a quality form of carbohydrates is really important to take on board the night before a race. For a marathon, 2-3 nights before this should be a focus. It ensures our body is stocked with energy to recruit for the race the next day. Since most road races are run in the morning, here are some examples of dinners to eat the night before (tried and tested!) and breakfasts for 2-3 hours before the gun goes off!
Personally, I like to keep it simple stupid. The night before some of my best middle to long-distance track races I eat a very simple take on fried rice:
-Long grain low G.I rice, the Dongara kind normally (the most important component, complex carbohydrates),
-Tuna/Salmon/Chicken or pork (lean protein, not a big fan of red meat the night before a race)
-Shredded carrot, steamed green beans (some simple veggies) - sometimes I roast up some potatoes, onions, zucchini etc.
-½ a small avocado sliced (Fats)
-Topped with soy sauce, a dash of sweet chili sauce and lemon juice + salt/pepper (for flavor!), sometimes I put mayo on my chicken.
I go into a lot more detail and explore the benefits of caffeine in my blog post. It's not just for the 5k distance - it's endurance fueling in general. The longer the race, the more fuel you'll need on board and the further out you have to plan this. Click the link if you want to give it a read:
https://larahamilton.com/5k-meal-plan/