What Should You Eat 48 Hours Before a Marathon?

You’ve put in the hard work. After weeks of training, race day is approaching. The last thing you want to do is mess things up by not dialing in your nutrition. You want to eat the right foods that will support you through the run, and make sure you avoid foods that might cause issues like cramping or nausea during the race. 

Should you focus on eating bagels and pasta all week? Do you need to carb load? What does that look like, anyway? Let’s break it down.

What should you eat the week before a marathon?

In the week leading up to your race, continue to eat balanced meals that contain carbohydrates, protein, and fat. Do not fall into the trap of thinking that because you’re in the taper you do not need as much food. The taper is when your body is able to rest and recover from the weeks of hard training. Your body cannot do this without adequate nourishment. 

Ideally, you have been increasing your carbohydrate consumption throughout your training cycle to support training. Our bodies’ stores of carbohydrates, known as glycogen, are limited - we are constantly breaking glycogen down into glucose, or sugar, to be used as energy. By training with a higher carb intake, we prime our muscles to be able to quickly access carbs for fuel during exercise.

While there are slight differences in glycogen storage across the menstrual cycle, females can store glycogen as effectively as males if their overall carb and energy intake is adequate (1).

Curious if you’ve been consuming enough carbs? According to the American College of Sports Medicine (ACSM), carbohydrate needs are as follows: (2)

• Light intensity: 3-5 g/kg (1.4-2.3 g/lb)

• Moderate intensity (1 hour/day): 5-7 g/kg (2.3-3.2 g/lb)

• High intensity (1-3 hour/day): 6-10 g/kg (2.7-4.5 g/lb)

• Very high intensity (>4-5 hours/day): 8-12 g/kg (3.6-5.5 g/lb)

The week before the marathon is not the week to try new foods. While this can be somewhat difficult if you are traveling to a race, try as much as possible to stick to familiar foods that you know sit well for you.

What should you eat 48-72 hours before a marathon?

As race day approaches, your nutrition should shift to focus on preparing your body for the hard effort that is coming. Two to three days before your race, your focus will shift to higher carbohydrate consumption.

For events that will be over 90 minutes of sustained exercise, the ACSM recommends 8-12 g/kg (3.6-5.5 g/lb) per 24 hours in the 36-48 hours leading up to the event - that’s right, per day (2).   

Carb loading at the Boston Marathon

You might be wondering – how will I eat that much food? It might help to write out a plan of what you’re going to eat and when, to ensure you are hitting this number. Keep in mind that you will be crowding out protein and fat sources in favor of carbohydrate sources, so think of it as eating differently rather than eating more. 

What does this look like, exactly?

Here is an example for a 140 lb person. First this person would calculate their carbohydrate needs: 3.6 grams of carbs x 140 lbs = 504 grams. This person’s goal is to consume 504 grams of carbohydrates per day for ~2 days leading up to the marathon. Carbohydrates can be found in grains, fruit, starchy vegetables, dairy, and sugar sweetened beverages.

Some carbohydrate rich food ideas (3):

• Bagel (50 g)

• Pretzels (50 g/2 servings)

• Applesauce (40 g/cup)

• Pasta (50 g/cup)

• Rice (50  g/cup)

• Sports drinks or powder (50 g/2 scoops)

• Bread (15 g/slice)

• Oats (50 g/cup)

• Apple (25 g/medium apple)

• Potatoes (50 g/large potato)

• Bananas (27 g/medium banana)

• Jam (15 g/Tbsp)

• Graham crackers (11 g/cracker)

• Honey (15 g/Tbsp)

In the 24 hours before your race, stick to foods that are higher in carbohydrates and lower in fiber and fat. This is especially true the closer you get to your race if you are prone to GI issues. You are aiming to fill your glycogen stores so that they are primed for the race. 

Here is an example day for this person (~500 g):

Breakfast: 1 cup oatmeal with 1 banana and 2 Tbsp honey (105 g)

Snack: Toast with 2 Tbsp jam + 24 oz water with 2 scoops Skratch  (95 g) 

Lunch: Bagel with 2 Tbsp peanut butter + 2 servings of pretzels (107 g)

Snack: 1 medium apple + 24 oz water with 2 scoops Skratch (75 g) 

Dinner: 2 cups pasta + 2 slices of bread (130 g)

Remember to stick with foods that you are familiar with and have eaten before running in the past. Do not overly stuff yourself at dinner the night before - you do not want to wake up with a stomach ache or feeling heavy.

What about hydration before a marathon?

While you are loading up on carbohydrates, do not forget about hydration. Being properly hydrated for your race will contribute to optimal performance. Carry a water bottle with you throughout the day and sip continually. While exact hydration needs will differ between people, you can generally gauge your hydration levels by making sure your urine is pale yellow in color.

What should you eat the morning of the race?

On race day, wake up with enough time to get in some food and water and to allow for digestion. Your race day nerves might blunt your appetite, so be sure to give yourself time to eat slowly. Around 1-4 hours before the race, recommendations are to include 1-4 grams of carbs/kg, or 0.4-1.8 g/lb. The further out you are from your race, the more food you can likely handle. 

In the hours before the race, we want to top off our glycogen stores with smaller amounts of easily digestible carbohydrates. For a 140 lb person, this would mean 56-252 grams of carbs in the 1-4 hours before the race starts.

An example of what meals might look like the morning of the marathon:

• 4 hours before the race: 1 bagel + 1 Tbsp jam + 1 banana (102 g)

• 3 hours before the race: 4 graham crackers (50 g)

• 1 hour before the race: 2 scoops of UCAN + 1 gel (75 g)

In terms of fluid intake, water recommendations are around 2-4 ml/lb in the 2 to 4 hours before exercise (2). This will allow you enough time to go to the bathroom before the race - take in a bit more fluids around 10-15 minutes before the race begins.

You should be practicing this day-of fueling during your long run training to be figure out what foods will fuel you through your runs, but will not cause you GI issues. Head to the starting line knowing that you are properly fueled and ready to give it your all! 

Questions about your race day fueling? Send me a message or set up a free discovery call!

References 

1. Burke LM, Hawley JA, Wong SHS, Jeukendrup AE. Carbohydrates for training and competition. Journal of Sports Sciences. 2011;29(sup 1): S17-S27.

2. Nutrition and Athletic Performance, Medicine & Science in Sports & Exercise. 2016; 48(3): 543-568.

3. US Department of Agriculture. FoodData Central.