Marathon Fueling: 5 Things to Practice Before Race Day

Marathon fueling isn’t something you figure out the night before your race, it’s something you train for just like the mileage.

The right marathon race nutrition plan can be the difference between cruising across the finish line and hitting the dreaded wall at mile 20 and barely finishing. In fact, I’d argue that 50% of marathon success comes down to nutrition.

The good news? You can work out the kinks well before race day. By using your long runs to practice racing nutrition strategies, you’ll step onto the starting line confident and well-prepared.

In this post, we’ll cover five specific things to practice during training so you can avoid GI distress, keep your energy steady, not hit the wall and run strong from the first mile to the last.

5 Things to Practice in Your Marathon Fueling Plan

You’re training your legs to handle the miles, now it’s time to focus on how to fuel for a marathon.

Race day nutrition isn’t just about what you eat that morning, it’s about the habits and strategies you’ve practiced for weeks beforehand. From carb loading to carrying your running gels, these are the details that can turn a miserable race into a strong, confident finish.

Let’s break down the five key marathon fueling strategies to work into your training so they feel second nature when you cross the start line!

1. Practice 1 Day of Your Carb Loading Plan

Step 1 for fueling for a marathon is carb loading the days leading up to it. The goal of carb loading is to optimize your glycogen (energy) stores. Along with a strong intra-race nutrition plan, carb loading is going to help you improve your race day performance and not hit the wall at all during your race.

During training, you’ll want to create your 3-day carb loading plan and practice 1 day of it. If you do a long run on Saturday, practice your carb loading plan on Friday. This allows you to identify what works, what doesn’t and then make changes before you carb load for real before your race!

When creating your carb loading plan, the goal is 8-12 g/kg/day (grams of carbs per kilogram of body weight per day). Plan for 3 meals and at least 2 snacks. Focus on low fiber carbs and drink your carbs to help you reach your carb loading goal!

Check out my list of The Best Foods for Carb Loading to help you plan out your carb loading menu.

2. Practice Your Dinner the Night Before

Another piece of marathon fueling is figuring out what you’re going to eat the night before your race. Take advantage of the night before your long runs to find a race day dinner that works really well for you. You’ll want to have plenty of carbs on your plate, some protein, some healthy fats and some color (fruit/veggies).

Some ideas for meals: pasta dishes, rice dishes, potato-based dishes and subs. My favorite pre-race dinner is pasta with salmon, a very small amount of veg and a carb-rich sports drink!

3. Practice Your Breakfast and Timing the Morning of

Just like you practice your pre-race dinner, it’s just as important to practice your race morning breakfast. Use the mornings of your long runs to test different foods and combinations so you can find a carb-rich meal that fuels you best.

Don’t just dial in what you eat, figure out when you’ll eat it. Training is the perfect time to see how long you need to digest before running, helping you avoid GI issues on race day.

Take a look at this guide on What to Eat Before a Half Marathon!

4. Practice Your Intra-Race Fueling and Hydration Plan

Proper fueling during a marathon includes these 3 parts: carbs, fluids and electrolytes, in particular sodium. This will help you maintain energy, optimize performance, delay fatigue and avoid bonking during your race.

You don’t just want to fuel and hydrate well on race day, it’s important to do this during your training too because the better you fuel and hydrate during training runs, the better you’ll perform during your training, setting yourself up for a strong race!

For marathon fuel, the general recommendation is to consume 60-90+ g/hour of carbs. For race day hydration, the general recommendation is 14-27 oz/hour of fluids and 300-600+ mg/hour of sodium, with salty sweaters likely needing >600 mg/hour of sodium. Work on building to goal during training!

If you plan to take the fuel and electrolyte drinks from your race course, purchase those same products and practice taking them during your training. I completely believe in the saying “nothing new on race day!”

For my first marathon, I took fuel on course that I never had before and almost ended up in the porta potty by mile 20. It definitely made the end of my race miserable. Don’t let trying new things on race day ruin your race, you’ve trained too hard for this!

5. Carrying your Intra-Run Nutrition

Training is the time to figure out how you’re going to carry your fuel, hydration and electrolytes. If you plan to race with a hydration vest, wear a hydration vest during training to get used to carrying the weight. If you plan to use a handheld, use it during training too!

If you plan to take cups on course, it may be beneficial to run a few shorter races during marathon training so you can practice taking cups on course and get used to it (it’s a lot harder and messier than most people think).

You’ll also want to know where the hydration stops are on course and how many cups you’ll need to take per hour to reach your fluid and sodium goals. Nailing down these types of logistics are key to having a smooth race day without any nutrition hiccups.

Bonus Tip: Practice Running in Your Race Day Outfit

Practice your entire race day outfit including your shoes, socks, shorts or pants, underwear, sports bra, shirt or tank.. I mean everything! Pick a long run to wear it all so you can catch any issues early and avoid race day surprises.

Before one of my marathons, I bought a new sports bra that I wanted to wear on race day and it felt comfortable in the store. Thankfully, I decided to test it on a long run first and I ended up with the worst chafing of my life! It wasn’t snug enough, so it moved around too much.

I was so relieved I discovered this before race day. A quick swap for a better-fitting sports bra saved me a lot of pain and made race day much more comfortable.

Marathon Fueling Takeaways 

Marathon day is the celebration of all your hard work, but success isn’t just about the miles you’ve logged, it’s also about the fueling and hydration strategies you’ve mastered along the way. 

By practicing your pre-race meals, timing of your race day breakfast and your intra-race fueling and hydration strategies well before the big day, you give yourself the best chance to have a strong race day.

Treat your long run like a dress rehearsal, make adjustments as needed and remember, nothing new on race day! The more prepared you are, the more confident and stronger you’ll feel when it matters most!

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