What to Eat Before a Race: Best Carbs for Performance and Digestion

Let’s be honest: many of us, including myself, love running in part because it allows us to eat a lot, including carbohydrates. Running burns a lot of calories in a short amount of time. When I was in college, I took this as a license to eat lots of carb-heavy foods: frozen yogurt, bagels, whole wheat pasta, pizza, and so on.

I’ve always been a healthy eater, so I was never overdoing it on sweets or refined carbs, but as I’ve researched more about nutrition, I have realized that not all carbs, not even all complex carbohydrates, are created equally in how they affect our bodies and our running.
Few things are more unpleasant than GI distress during a race or even a normal training run. Chances are that repeated episodes of side cramps, the runner’s trots, and the like are an indicator that something is amiss with your gut or your diet. {find more tips on avoiding the dreaded runner’s trots!}

What you eat the day before and the day of a run directly impacts how your stomach will behave during your workout. Even more so, your nutrition and fueling during the entire length of a training cycle will affect your GI system on race day.

Eating the best types of carbs for you will definitely help you achieve your race day goals and, most importantly, enjoy your race!

What to Eat the Night Before a Race

We often talk about race morning, but what to eat the night before a half marathon is hugely important. It’s going to play a major role in how your stomach acts the next day. While I am no nutritional expert, I highly recommend avoiding heavy pasta or bread dish before a race.

Why skip the traditional pasta dinner?

• Refined flours have a high glycemic index, which will result in a spike and then crash in your blood glucose levels.
• Whole wheat flours are high in fiber, which you should incorporate into your normal healthy eating, but may not want before a race.
• Even if you do not have celiac disease or gluten intolerance, you may have a minor gluten sensitivity that leads to inflammation, especially when you may be already experiencing more inflammation than usual from high training volume and intensity.

Inflammation negatively affects many aspects of your health and can cause bloating, constipation, nausea, indigestion, and other distresses to your stomach.

The stress of training and the anxiety surrounding the race can make your stomach extra sensitive, so a large serving (or, realistically, multiple servings) of gluten in your pre-race meal may harm more than help your running.

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Instead, select less processed sources of carbohydrates from whole foods, which will have low glycemic index and therefore provide a regulated and steady stream of glucose into your bloodstream as you digest them. Steady blood sugar will decrease your likelihood of waking up famished before your race or bonking during your marathon.

• Consider a sweet potato and salmon, maybe even a small salad
• Spaghetti squash with chicken or lentils
• A turkey sandwich

Notice all of these are simple, easy to digest, which means you don’t have to worry about waking up with a heavy stomach the morning of your race.

Read more about the myths of carboloading to feel better about your choices!

Which leads us too…

What to eat before a race?

Let’s talk more about the best carbs for race morning, along with additional tips on what to eat the day before a marathon.Bananas
Bananas are one of the best foods for runners, and for a good reason. These easy-to-digest and completely unprocessed fruits will fuel you with 31 grams of carbohydrates in the form of natural sugars.

Additionally, bananas contain potassium and magnesium, which are two of the electrolytes your body requires for running. A banana is my favorite pre-run snack, since one has enough carbs and calories to fuel my run but will not weigh down or upset my stomach.

Brown Rice
1 cup of brown rice will energize you with 45 grams of carbs! Rice has a very low glycemic index, which means that it will provide you with lasting energy. It’s also very gentle on the stomach; think of the BRAT (banana, rice, applesauce, toast) guideline for eating when you have an upset stomach.

If you’re worried about fiber before a race, stick with white rice. You can have rice for dinner or even breakfast before a race.

Rolled/Old-Fashioned Oats
Skip the sugary cereal and opt for heart-healthy oats instead. ½ cup of oats (or 1 cup cooked oatmeal) contains 27 grams of low glycemic carbohydrates.

Enjoy a bowl of oatmeal before your race, although make sure you allow a couple hours for digestion since oats are higher in fiber and slowly convert to simple sugars once digested. Or, enjoy a bowl of savory oats with some eggs the night before the race for a satisfying meal!

Potatoes
Potatoes have undeservedly earned a bad reputation over the past few years, thanks to the popularity of low-carb diets such as Atkins and Paleo. However, the potatoes themselves are not unhealthy, but rather the ingredients and fats added in the preparation of many potato dishes.

The humble potato, however, is a naturally gluten-free source of carbohydrates. One medium russet potato contains 38 grams of carbs along with plenty of potassium, magnesium, and vitamin B-6. Additionally, potatoes are gentle on the stomach, which is ideal for runners who get race-day nerves and want to avoid GI distress.

If you do not like white potatoes, choose the delicious and healthy sweet potato. Enjoy a plain baked potato (add a bit of Greek yogurt instead of butter or sour cream) as part of your pre-race dinner. You can even eat a potato as your pre-race breakfast, as it is easily digestible, or cut up a baked potato into small chunks and carry them in a baggie as mid-race fuel.

Grains
Various whole grains, including quinoa, farro, amaranth, teff, polenta/cornmeal, and millet. These grains compose up to 70% of the diets of the super-fast Kenyan runners.

Now this has largely been focused on what to eat before a race, but here are some great runner snacks or ideas for what to eat before a run.

Carbo-Loading Tips

In the days of carbo-loading before a marathon, try to vary your carbohydrate sources as much as possible. Avoid simply eating toast for breakfast, a sandwich for lunch, and pasta for dinner, as this will not only leave your stomach feeling heavy and your digestive system backed up, but it will deprive your body of the essential nutrients needed for running a strong race.

Carbo-loading doesn’t mean gorging. Here’s what it could look like:

• oatmeal with fruit for breakfast
• rice with veggies at lunch
• baked russet or sweet potato with your choice of protein and a small side salad at dinner

Not only will this provide your body with a steady stream of carbs to top off your glycogen stores, but you will also have enough potassium, iron, magnesium, vitamin B-6, and other essential vitamins to fuel you through the race.

If you eat a healthy diet throughout training (which you should!), then you don’t want to stress your body right before a race by drastically changing your diet and depriving yourself of the usual nutrients.

Experiment During Your Long Runs

The best carbohydrate sources are ultimately those that work best for your body, but discovering which ones work best requires some trial and error.

Treat your long runs like trial races when it comes to every aspect of fueling. Use your training journal to record what you ate before each long run and how it affected you, so that you can easily assess near the end of your training cycle what worked and what did not. {Amanda’s note: After your well earned post run selfie make it a habit to log this info!}
Night before long runs
Eat what you anticipate you will eat the night before the race, consider this your practice pre marathon meal. This allows you to evaluate how the meal sat on your stomach and impacted your energy levels well before you toe the starting line.

Expand beyond the typical bowl of pasta to find what truly works best for you; you may feel good after pasta, but run even better after eating brown rice or a baked potato.

Pre-run Breakfast
Even if it means waking up extra early {allowing your food to digest more} and then going back to bed for a bit, eat before your long runs what you plan to eat before the race.

{Amanda’s note: Remember on race day you are going to be pushing harder than many of your long runs, so digestion will be further reduced. You need plenty of time pre-race for your body to do the work.}

During the run
On the run itself, take your gels at the exact intervals as you will on race day. Note how these affect your stomach, and experiment with different whole foods, gels, and timing until you find your perfect fuel.

If gels or chomps have upset your stomach in the past, use your training runs to experiment with different brands or even whole foods. A lightly salted plain baked potato, dates, raisins, crystallized ginger (great for soothing stomachs also), and bananas are easy to eat and digest while running and provide your body with a plenty of carbohydrates.
Checkout these additional whole food fuel options >>

Have you found your perfect pre-race fuel yet?

Any fuel experiments that went horribly wrong?

Laura is a distance runner, recipe developer, running science and nutrition nerd, and writer in the Seattle area with a passion for homemade and healthy food. When she’s not training for the Portland Marathon or testing out a new recipe for her upcoming eCookbook, she loves to hike in the mountains with husband Ryan and puggle Charlie.

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