Every meal is important, but no meal is more important than the one before a race. Choosing the wrong foods, eating too much or too little, or eating at the wrong time can affect your performance and possibly ruin your race, or at least make your performance less than optimal. Eating the right pre-race meal at the right time ensures that all your hard training doesn't go to waste.
The morning of a race, eat a good breakfast and make sure you are completely finished at least two to three hours before the race. You want the meal to be digested and leave your stomach by race time. If you get hungry before the race have a quick energy bar.
At least 80 percent of the calories you consume in your pre-race meal should come from carbohydrates. Keep your protein, and especially your fat and fiber consumption low. These nutrients take up space that are better utilized by carbohydrate. Also avoid gas-producing foods such as onions.
Choose foods and drinks that are not only easily-digested, but also easily-consumed--especially if you're prone to nervousness.
Also, be sure to keep drinking water in small amounts all the way up to race time. Possibly the single biggest issue which could negatively impact your race is dehydration. Losing as little as 1 percent of your body weight in fluid can decrease performance by up to 10 percent. A priority should be to start the race with your fluid reserves at full capacity. Stay away from dairy products before a race (such as milk and eggs) as they take longer to digest than carbohydrates and are better for post-race refueling.
Some recommendations:
Bagel
A bagel makes an excellent pre-race breakfast food, not only because it's rich in carbohydrate, bland and easily-digested, but also because it's something many runners eat for breakfast routinely, hence familiar. Eat it dry or top it with something low in fat such as a light smearing of reduced fat cream cheese or peanut butter.
Banana
Bananas are almost all carbohydrate. A large banana contains more than 30 grams of carbohydrate, just one gram of protein and no fat whatsoever. Bananas are also high in potassium (400 mg), which is lost in sweat during running. As mentioned above, their softness and light taste make them easy to consume even with pre-race nerves, and their natural "wrapper" makes them handy for eating on the road.
Whole grain bread toast with peanut butter (or sunbutter)
Whole grains are better than white bread as the fiber and protein from the bran and germ (whole grain bread) provide a more constant source of energy, which will keep you going long after the energy from refined grains (white bread) is gone. The fiber in the bran can also mean whole-grain breads help people feel full longer. The peanut butter will help you sustain your energy during the race.
Whole grain waffles with bananas on top!!!! (A Coach Milbourn favorite)
Oatmeal
Like bananas, oatmeal is almost pure carbohydrate, plus soft and light in taste. It is also the most filling food among the five best pre-race foods, which is good for those wanting something substantial in their belly before they head out to burn a few thousand calories. Some runners also prefer to eat a real breakfast food for breakfast, and oatmeal certainly provides that. Slice up a banana, put it on top of your oatmeal, and you are all set.
Other ideas: apples (although the acid may bother some), cherries, and mangoes.
Stay away from protein foods like meat or eggs-they do not digest very fast.
Also, no white bread or sugared cereal-the sugar will give you a quick boost of energy and then you will fall off just as fast.
Good Pre-Race Snack: Energy Bar
Energy bars such as PowerBar and ClifBar are made to be eaten before exercise. Most are very high in carbohydrates and low in fiber, fat and protein. The better bars also contain useful amounts of sodium, potassium and the antioxidant vitamins C and E. A cappuccino flavor PowerBar, for example, contains 45 g of carbohydrate, 110 mg each of sodium and potassium, 35 percent of the recommended daily allowance of magnesium and 100 percent of the RDA of vitamins C and E.
There's a huge variety of energy bars on the market--some are better than others. Choose one that's close to the PowerBar formula I just outlined. Avoid the high-protein, low-carb bars that have become popular in recent years. The advantage of the wide selection of bars on the market is that it's easy to find one you like and can eat without unpleasantness before a race. Pay attention to texture too. Some bars are very chewy, and for some runners eating chewy foods tends to exacerbate the stomach churning that's associated with pre-race nervousness.
Any combination of what is listed above should do the job!!!!!!
(Excerpts from Active.com, RunnersWorld.com, and Coach Milbourn)