Ask The RDN: How To Not Screw Up Your Pre-Race Breakfast

Your GI system is unique to you, and it can be upset by many things. But carefully calibrating your pre-race breakfast can prevent mishaps.

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What should I have to eat before races to make sure I have enough fuel, but not . . . too much?

Ah yes. The midrace bathroom break.  As you practice immaculate Leave No Trace ethics, thoughts may run through your head: Was it the hamburger last night, maybe the coffee this morning, or what the gel you just slurped? It could be one – or all – of these things. Everyone has a different tolerance for specific foods. Anxiety itself can even trigger GI distress.

The point of this is not to scare you away from eating (PLEASE, do), but to encourage you to experiment, to know that at some point, you will inevitably fail to fuel perfectly and, therefore, give yourself a chance to practice your cat hole technique.

Luckily, there are some guidelines you can try and follow to see if you can come up with a good pre-race meal for yourself:

1. Fuel Mindfully the Week Of Your Race.

Ideally, you are going into your race with glycogen stores that overfloweth. Race week is not the time to cut back on calories and carbohydrates or try out that new juice cleanse. Instead of relying on the dinner and breakfast before your race for an epic carbo-load, think of the week before as a chance to eat a bunch of great, somewhat-epic meals.

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2. Aim For A Breakfast Of 200-500 Calories

This will help top off your tank so that you can be ready when the gun goes off, but not be so much that it causes GI symptoms.  Keep in mind that some may be able to tolerate more food, but once you start to run, the blood is diverted away from your digestive system to your working muscles, making it a lot harder to break down a bigger amount of food. This may not sound like a lot, but remember: chances are, you’re going to be adding additional fuel during your race, so you don’t need to be at the finish line already containing all the calories you’ll need.

3. Include 15-20 Grams Of Protein

This will help prevent too much of a blood sugar spike and drop and will allow for the body to preserve muscle a bit longer during the race. A dollop of nut butter is great, but we’re not aiming for gym-mirror selfie levels of protein here.

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4. Minimize Fiber And Fat

An hour before you try to PR your 50k is not the ideal time to surprise your gut with a load of fiber. Sorry, avocado toast. Aim for simple carbohydrates like white rice, white bread, quick-cook oats, or waffles.

5. Practice Ahead Of Race Day

You are a special, gastro-intestinal snowflake. What works for your gut may be different than the fresh, organic alpine berries that fuel Emelie Forsberg. That’s ok! Typical triggers for stomach upset are things like dairy, eggs, acidic juices, high fructose foods, and coffee. To minimize the risk of surprise GI distress, practice your race-day breakfast before key long-runs or workouts.

6. Time It Right.

Try and eat a pre-race meal at least 2-3 hours before the race begins.  If you are within an hour of your race, stick to something extra simple like the liquid calories in a smoothie or a simple PBJ.

Some Pre-Race Meal Options

Option 1:

  • Bowl of white rice
  • Banana
  • 2T peanut butter
  • Glass of almond milk with a little bit of protein powder

Option 2:

  • 2 toaster waffles
  • 2T peanut butter
  • 1 T maple syrup
  • Banana

Option 3:

  • Bagel
  • 2T peanut butter
  • Jam
  • Berries
  • 1 glass oat milk with a little bit of protein powder

Do you have a question for our RDN? Send your trail-running-nutrition quandaries to

Kylee Van Horn is a licensed Sports Registered Dietitian and competitive trail runner.

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