Marathon Week Nutrition – Strategies to Run Your Best Race!

Sioux Falls Marathon weekend is fast approaching!

On Sept. 10, runners from Sioux Falls and beyond will toe the starting line to run the Miracle 5K, half marathon, full marathon or marathon relay. This year, the race has some big changes, including a new start/finish location inside the Denny Sanford Premier Center.

If you’re running one of the Sioux Falls races, now is the time to really start thinking about your race week nutrition.

You don’t have to be an elite runner to apply some science-based recommendations about carbohydrate loading and nutrition to your race week planning – your meals in the week leading up to a big race can really make or break your performance, no matter what your race goals are.

The Lowdown on Carbohydrates

When you run out of carbohydrates on a run, you can “hit the wall” or get that feeling of fatigue, where you think you can’t take another step. Runners are notorious for eating a high carbohydrate diet, but during race week, it’s important to note who needs to pay special attention to carbohydrates, why they’re needed, when it’s necessary and how many grams of carbohydrates are needed.

  • Carbohydrate loading is the traditional practice of runners focusing on eating carbohydrates in the days leading up  to their race to optimize their glycogen stores.
  • Runners who are racing over 90 minutes should be thinking about carbohydrate loading. When we eat carbohydrates, it is stored as glycogen in the liver and muscles, and our muscles use this fuel primarily during a race. Having high energy stores won’t necessarily make you faster, but it can help you delay fatigue.
  • Research shows that as few as 2-3 days of carbohydrate loading in addition to rest (tapering) can optimize glycogen stores! You’ll find so many methods for the best way to carbohydrate load, but one of the easiest ways is to make sure your mileage is low the week before your marathon, and focus on increasing your carbohydrate intake 2-3 days before your race.
  • Start several days before your race by increasing your normal amount of carbohydrates from 55-65% to 70% in those several days before your race. This can easily be done by increasing your portions of carbohydrate foods (add an extra serving of carbohydrates during the day) and decreasing your protein and healthy fats.
  • This doesn’t mean eliminating protein and fat completely for carbohydrates – you still need some good balance to feel great on race day!
  • The numbers end up being 4.5 – 5.5 grams of carbs per lb. body weight, sounds like a lot or carbohydrates…so just focus on those whole grains, vegetables, fruits, potatoes/sweet potatoes, and dairy foods as tolerated several days before the race by adding a serving of those foods at each meal and decreasing protein and fat servings.
  • You don’t need to eat extra food or more calories – you’ll be less active during this time, so try to keep your portions and amount of calories you’re eating the same and change the composition of your plate to focus on carbs. Some runners tend to think they can eat whatever they want the week of their race, or focus too much on carbohydrates and show up to race day feeling lethargic and heavy. Save that ice cream/pizza/donuts/whatever for after the race!

Many runners experience moderate weight gain of 1-3 lbs. due to the fact that glycogen stores water along with it. If you experience this, don’t worry! Your body is just preparing itself for race day.

The Day Before Your Race

The day before your race, your eating plan should be to eat throughout the day, focusing on carbohydrate rich foods because you aren’t going to be able to fill your glycogen stores in just one big pre-race meal.

Choose easy carbohydrate options at each meal – 

  • Grains such as rice, oatmeal, quinoa, pasta
  • Baked and roasted potatoes and sweet potatoes
  • Bread/buns/toast
  • Pancakes
  • Bagels
  • Tortillas
  • Yogurt
  • Juice/sports drinks

Fruit and vegetables are also good carbohydrate options, but watch the fiber content! Bananas are always a good go-to fruit, and you can cook your vegetables to make them easier to digest.

Instead of the traditional heavy pasta dinner, try eating your main pre-race meal for lunch the day before your race to ensure you have enough time to digest that food, and try having a lighter carbohydrate-rich dinner and a carbohydrate snack before bed.

Pre-Race Breakfast

The morning of a half or full marathon, you should ideally wake up 3-4 hours before  your race to top off those glycogen stores with carbohydrates by eating a meal that contains mostly carbohydrates with moderate protein and fat. You want this meal to hold you over throughout your race without weighing you down, so the closer you get to the race, the smaller your meal becomes.

Again, stick what has worked for YOU in the past and don’t stress out over it!

  • 1-4 hours before: 1-4 grams of carbohydrate per kilogram body weight (150 lbs/2.2 = 78 kg)
    • 1/2 cup oatmeal cooked in 1 cup milk, a banana, peanut butter, raisins, sweetened with honey and cinnamon and a dash of salt
    • A turkey sandwich
    • 1/2 or full large bagel with peanut butter, honey and a banana
    • 2 pieces of toast with banana and honey, some sports drink or juice
    • 1 Nature Valley granola bar and a banana

There is a lot of research and information on carbohydrate loading, with results showing it is beneficial and other results showing it doesn’t make a difference.

The bottom line is – if you can eat extra carbs in the days leading up to your race, it isn’t going to cause you any harm and you might actually be able to help your performance, so it’s worth a try!

Nutrition for a 5K or Short Relay Legs of a Race

If you’re running a 5K or marathon relay, you’ll be running pretty hard for those 3.1 miles or however long your relay leg is. As mentioned above, you don’t necessarily need to carbohydrate load or focus on diet during race week as much as a half or full marathon runner, as you will likely be running under 90 minutes total and your body has plenty of glycogen stored away to get you through your race.

Follow the same “day before” plan as a marathon runner, though you probably won’t need as many calories. You should consider what you eat the day before the race – focus on eating healthy carbohydrates (potatoes, whole grains such as whole grain bread, pasta, rice, quinoa, fruits and vegetables), lean proteins and limit the amount of fats you eat.

Again, avoid high fat and high fiber foods the day before if you know your stomach is sensitive – cook your vegetables, peel your fruit or choose fruit juice, and avoid those high-fiber grains and vegetables.

A big breakfast on race morning might cause stomach upset, so instead, try to eat at least an hour before the race. Many people opt for easy-on-the-stomach carbohydrate foods, like a banana with peanut butter, toast and jam, a granola bar and a piece of fruit, or some sports drink/juice. Eat enough to hold you over throughout the race, but not too much that you’re feeling stuffed and heavy at the starting line.

Rules to remember on race week:

  1. Now isn’t the time to experiment. You might have some tried and true pre-run meals you know sit well with you – go with those foods and relax!
  2. Everyone is different! Some people might be able to handle high fiber, high fat foods the day before a run or race, but others may do better with a higher carbohydrate, low fiber diet. You know yourself best, so if your running partner is eating a huge plate of pasta and you haven’t eaten that before your run before, do yourself a favor and stick to foods you know!

If you have any last-minute race nutrition questions before your race, give the Sanford Sports Science Institute Nutritionist a call at 605-312-7878 or e-mail her at