Best Carbs for Runners & Endurance Athletes: Tips to Increase Your Intake

As an endurance athlete, you likely already know that carbohydrates are key to performance. They’re the body’s preferred energy source for all forms of exercise, and especially for long duration and moderate to high intensity sessions.

Carbs also play a critical role in supporting health. Matching your carb intake to your individual needs helps to preserve muscle mass, protect your bones, promote iron absorption, regulate hormone function, provide a primary energy source to the brain, maintain GI function, and influence heart health, among other things.

Eating enough carbs, especially in a way that feels enjoyable and sustainable, can be a challenge for many athletes. If you’ve ever found yourself bonking mid-training session or feeling sluggish while going about the rest of your day, you might not be fueling optimally.

In this article, you’ll learn how many carbs per day you should be consuming based on your activity level, the best carbs for runners and other endurance athletes, plus some easy ways to increase your carb intake to feel your best during training, racing, and in your everyday life.

Best carbs for runners and endurance athletes: how to increase your carb intake

Athlete Performance Plates & Carbohydrate Guidelines

Carbohydrates are stored in your muscles and liver as glycogen, which serves as your primary fuel during exercise. The harder and longer you go, the more glycogen you break down into glucose to burn for energy.

However, your ability to store glycogen is limited, which means you need to consume outside sources of carbs to prolong available stores and keep energy levels strong. Otherwise, you risk crashing and burning in training and racing, and feeling like hot garbage the rest of the day too.

Your carb requirements will fluctuate based on your activity level. You can learn how to adjust your intake based on what exercise you did that day as well as your current weekly training volume by using athlete performance plates.

You can also use research based guidelines to estimate daily carb targets. Endurance athletes typically need anywhere from 5-12 grams of carbohydrates per kilogram of body weight per day, depending on training, intensity, and duration.

Since that is a huge range, here’s how to break that down further:

Low training volume/intensity (0-60min/day of easy effort): 3-4g/kg of carbs per day
Moderate volume/intensity (~1-2 hr/day of easy effort or <60min of high intensity): 5-7g/kg carbs per day
High volume/intensity (~2-3 hr/day of easy-effort or 1-2hr of high intensity): 6-8g/kg carbs per day
Carb loading or very high volume/intensity: 8-12g/kg carbs per day

The main takeaway is that the more you train, the more carbohydrates (and overall energy and other nutrients) your body needs. Experiment with and slowly work up to these recommended amounts, while also paying attention to how your body feels (including hunger and fullness cues).

Best Carbs for Runners and Endurance Athletes: 5 Simple Strategies to Increase Your Intake

If you calculate out your carbohydrate needs and that number seems really high compared to what you’re currently consuming, you’re not alone. A large number of clients that I work with are undereating carbs, but the good news is that this is a fairly easy fix!

Note that the best carbs for runners and endurance athletes are the ones you enjoy, tolerate well, and can access easily. With that in mind, here are 5 simple ways to increase your carb intake:

1. Begin Your Day with a Carb-Rich Meal

Your morning meal sets the tone for the day, so don’t skip or limit carbs! What you choose will depend on if you’re about to exercise, going later in the day, or if it’s a rest day.

As a general rule, the more time you have and the longer the session, the more carbs you need. For a more specific guideline especially for exercise lasting >60 minutes, go for 1-4g/kg of carbs 1-4 hours prior to exercise.

For a pre-exercise meal or snack, choose mostly carbs (optional to include protein and fat, if you have time to digest), such as:

Oatmeal with banana, optional peanut butter
Bagel with peanut butter and jelly
Pancakes or waffles with syrup

If you’re exercising later in the day or have >2-3 hours to digest, choose a carb-rich meal (2-4g/kg 2-4 hours before exercise) with around 20-40g of protein and some fat. Here are some examples:

Loaded oatmeal bowl with nuts, fruit, honey, and a big scoop of Greek yogurt
Whole-grain toast or bagel with peanut butter + eggs + fruit
Yogurt bowl with granola, fruit and nuts
French toast with PB, fruit, syrup (use 1 egg per 1 slice bread for egg mixture)
A breakfast burrito with rice, beans, and eggs or tofu

Want more pre-exercise fueling advice?

Here’s a free Fueling Before Exercise Mini Guide that you can download
This article provides a more detailed breakdown of what to eat prior to a short session
This article gives specific guidance on how to fuel before an endurance activity

Lastly, remember that you still need plenty of carbs even on a rest day! If you are in the middle of a training cycle, that means you’re recovering from one session and preparing for the next, and need to fuel appropriately. Again, Performance Plates demonstrate how to adjust carb intake on different training days, including days off from exercise.

If you're afraid to add more carbs (e.g. fear of weight gain is a common reason I hear), I encourage you to explore this further with my free Food Rules, Fears and Beliefs Worksheet. This may also be a good reason to seek professional help from a Sports Dietitian.

2. Snack with Intention: High Carb Snacks for Athletes

Instead of reaching for low-carb options like only nuts, cheese or a meat stick, incorporate high-carb snacks between meals to sustain energy.

Great choices include:

Trail mix with dried fruit and pretzels
Cheese or meat stick or edamame + large banana
Whole grain crackers with cheese and/or hummus + grapes
Peanut butter and jelly sandwich (swap sliced bread for a bagel to boost carbs futher)
Banana with nut butter and honey on toast

Try adding a glass of 100% fruit juice (e.g. OJ, tart cherry, pomegranate etc) or chocolate milk or soy milk to your snack to further increase your carb intake. For example, just 8oz of juice adds 30 grams of carbs!

3. Make Carbs the Star, Not a Side Dish: High Carb Meals for Athletes

When planning meals, build them around carb-rich foods rather than treating them as an afterthought. Here are some strategies for creating high carb meals for athletes:

Build a bowl with your favorite grain (e.g. rice, quinoa, farro, etc), veggies, and lean protein instead of just having a lettuce or other greens-based salad
Swap cauliflower rice for regular rice or starchy veggies (peas, corn, potatoes)
Enjoy pasta whenever you like, not just before a long session or race day, and add veggies, a lean protein, and your favorite sauce to round out the meal
Regularly include other carb-rich foods like tortillas, bread, bagels, grains, starchy veggies (peas, potatoes, corn), beans/legumes, fruit, and dairy

You can't expect to meet your daily carb goals if each meal doesn't feature carbs.

4. Drink Your Carbs

If you struggle to eat enough solid food sources of carbs, liquids can be an easy way to top off glycogen stores. This strategy is a life saver during periods of high training volume as well as when carb loading.

Here are some great liquid carb options for athletes:

Smoothies with fruit, yogurt/kefir, and oats
Chocolate milk or soy milk (almond/oat milks don’t have as much protein)
Sports drinks (i.e. with electrolytes and carbs) before, during, or right after long or hard training sessions
100% fruit juice paired with a meal or snack

If you want to get fancy, here's my favorite mocktail recipe for athletes: Mix pomegranate juice (4-8oz) with lemon or lime seltzer to taste, with an option to add some coconut water for a potassium boost. Quick, delicious, and packs in carbs plus antioxidants!

5. Fuel with Carbs During Long or Hard Training Sessions and Races

Once you hit the 60-minute mark in training, your body benefits from exogenous (i.e. outside) sources of carbs. A general guideline is to take in 30-90g+ of carbs per hour, with the exact amount depending on duration, intensity, and what you can tolerate.

Here are some easy options to include during exercise:

Energy gels or chews
- Products vary widely in carb content, with anywhere from 15 - 50g per serving, and also may or may not contain sodium, so check labels closely
Sports drinks that provide carbs and electrolytes (primarily sodium)
- Drink mixes also vary widely in carb and sodium content, with many brands offering regular and "high carb" fueling options
Solid foods such as fig bars, pretzels, waffles, energy bars, or other easy-to-digest carb-rich solid foods

You may also notice a benefit to including carbs like a sports drink during shorter, intense efforts. Experiment and see what feels good to you!

Want to learn more about fueling during exercise? This article covers everything you need to know about fueling during longer training sessions and races (i.e. >60-90 minutes), including how to train the gut.

How to Increase Carb Intake: Putting It All Together

Fueling well with carbs doesn’t have to be complicated. The key is to make carbohydrates a consistent part of your meals and snacks, rather than an afterthought.

Gradually increase your carb intake in your everyday diet, and be sure to include additional fluid along with your carbs. That’s because carbs are stored with water in the body, so you need extra fluid to maintain your hydration status.

If you’re struggling to hit your carb targets, start by adding an extra carb-rich snack or increase your portion of a starch at one meal (e.g. 1.5 cups of cooked pasta instead of 1 cup), and slowly work your way up. Similarly, train your gut by slowly increasing carb intake during exercise.

Lastly, I want to emphasize again that the best carbs for runners and other endurance athletes are the ones you will actually eat! Play around and figure out which carb-rich foods and products feel good in your body and allow you to hit your carb intake goals.

By prioritizing carbs in your diet, you’ll have more energy, recover faster, and perform better in training and on race day. So go ahead - embrace carbs and experience the benefits!

Other Nutrition Resources for Athletes

I encourage you to check out my other online nutrition resources, many of which are free!

I currently offer 7 FREE nutrition downloads on a variety of topics
I am over 100 episodes deep into The Eat for Endurance Podcast
I offer a library full of low-cost nutrition mini guides, as well as a race-nutrition masterclass

Want a Personalized Fueling Plan?

As an experienced sports dietitian, I can help you tailor your carb and other nutrient intake to match your training needs and goals. I offer a variety of online nutrition coaching services to fit every budget.

My monthly membership, Fuel for Life Crew, gets you direct access to me and a supportive community of active people like you for all your nutrition questions. You also get live monthly masterclasses on a variety of nutrition topics and access to my full online library of resources, for just $30/month (cancel anytime).

If you're ready to go all-in to transform your nutrition, health, and performance and get more personalized support, 1:1 nutrition coaching is for you. To get started, book a discovery call here.

NEW: Fuel for Life Crew nutrition membership! Learn more here.