Marathon Carb Fueling Guide + A Cherry Watermelon Recovery Smoothie

When you’re training for a big race like a half or full marathon, figuring out how many carbohydrates you should be eating day to day can be pretty confusing. So I’ve taken the guesswork out of it and made you a step-by-step guide to help ensure you’re getting the right amount of carbs. When it comes to giving your body the nutrition it needs, every day counts–not just the few days leading up to the race! And not all carbs are created equal; the healthiest options are going to be fruits, whole grains, beans, lentils, and vegetables. Stay away from highly processed and refined carbs like granola bars, cookies, ice cream, and white or enriched breads and grains. Just say no to foods with a long list of ingredients, and instead reach for something that grew out of the ground!


Carbohydrate Fueling Guide

During training:

Step 1: To find your weight in kilograms (kg) divide your current weight in pounds (lbs) by 2.2

  • Ex. 150 lbs/2.2=68 kg

Step 2: Pick your desired carbohydrate range based on your running event

  • For a half marathon or lower intensity (walking) full marathon training, or people with a goal of weight loss
    • 3-5 grams carb/kg/day
  • For full marathon training
    • 5-7 grams carb/kg/day—days when training around 1 hour per day
    • 6-10 grams carb/kg/day—days when training 1-3 hours per day


Week before event:

  • Days 1-3: maintain your usual training carbohydrate intake
  • Days 4-6 carb loading: aim for between 7-12 grams carb/kg
    • 7 grams carb/kg being more conservative for carb-loading, but sufficient for a half marathon. One day of increased carb intake is adequate for a half marathon (and one day is easier than three!)
    • 10-12 grams carb/kg being recommended for maximum glycogen storage for a full marathon
  • Day 7: Race day
    • Eat 1 gram carb/kg for each hour until your run up to 4 hours; so, if you wake up 2 hours before the marathon, eat 2 grams carb/kg.


I recommend reading food labels to ensure you are getting the right amount of carbohydrates day to day. Using an online or smart phone app like LoseIt or MyFitnessPal is a really simple and convenient way of ensuring you are getting adequate carbs.


And I can’t do a post about carbohydrates without sharing an incredibly refreshing muscle recovery smoothie (it’s actually more like a slushy)! I used watermelon and red tart cherries, two fruits that are shown to have health benefits for endurance runners. Watermelon contains L-citrulline which is supposed to help relieve post-exercise muscle soreness. The red tart cherries are a potent source of antioxidants and help fight muscle inflammation.



{Cherry Watermelon Recovery Smoothie}

Recover quickly from your long run with this icy smoothie! It contains the recommended 3:1 protein to carb ratio for recovery. Watermelon helps with post-exercise muscle soreness, and the cherries fight inflammation. The chia seeds pack omega-3 fats and help with fat-soluble vitamin absorption. 

cherry watermelon smoothie


2 cups seedless watermelon

1 cup frozen red tart cherries

1 5.3 oz container plain nonfat Greek yogurt

1 tbsp chia seeds

pinch of unrefined salt

2 handfuls of ice cubes


Substitution: If you don’t don’t like Greek yogurt, you could use a scoop of favorite whey or vegan protein powder–about 15 grams worth to get an equivalent protein amount.


Combine all ingredients in a blender; blend until smooth.


Nutrition info for entire smoothie:  344 cal, 5 g fat (0 g sat fat), 68 g carb, 20 g pro, 8 g fiber



One Response to Marathon Carb Fueling Guide + A Cherry Watermelon Recovery Smoothie

  1. Mary Smith says:

    Hey, I thought this was a nice blog. Thank you for posting.

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