Running Nutrition: An Expert Coach’s Guide To Healthy Fueling

The importance of nutrition for runners cannot be understated. 

Although we can’t overlook the importance of following a good training plan, long-distance running also requires proper nutrition with a balanced diet that has adequate calories, carbohydrates, proteins, healthy fats, vitamins, minerals, and hydration.

In this guide to nutrition for runners, we will discuss macros for marathon running and running in general, as well as the best foods to eat in a healthy running nutrition program.

We will look at:

Ready? 

Let’s jump in!

How Much Should I Eat As a Runner? 

As a Certified Nutrition Coach and a Certified Endurance Nutrition Coach, the most common questions the runners I work with ask is: “How many calories do runners need to eat?”

The nutritional needs of any long distance runner will depend on their body size, sex, how much training they are doing, and their body weight goals.

Runners who are trying to maintain their body weight need to be in an energy balance. This means that the runner’s nutrition plan has to provide the same number of calories that the runner is burning in a day.

Caloric expenditure, also known as total daily energy expenditure (TDEE), is the sum of the calories burned through your planned workouts, daily physical activity outside of running, the calories you burn in digesting food, and your basal metabolic rate (BMR).

Your BMR is the largest component of your total daily energy expenditure. You can estimate your BMR with online calculators such as the one here.¹Basal Metabolic Rate (BMR) Calculator. (2012). ACTIVE.com. https://www.active.com/fitness/calculators/bmr

‌You can also estimate your caloric needs based on your total daily energy expenditure (TDEE) here.²Body Weight Planner | NIDDK. (n.d.). Www.niddk.nih.gov. https://www.niddk.nih.gov/bwp

‌If you are trying to gain weight, you need to be in a caloric surplus, which means that your diet plan has to provide more calories per day than you are burning.

In contrast, if you are trying to lose weight, you want to be in a caloric deficit.

However, because running requires a tremendous amount of targeted nutrition to support running performance, muscle repair, and fuel for your workouts, it is very important to work with a sports nutritionist or a registered dietitian if you are trying to lose weight during marathon training. 

Generally, I recommend that marathon runners focus either on running performance and their marathon training or running for health and weight loss without taking on a dedicated training plan. 

Trying to do both at the same time can increase your risk of injury through underfueling, or may not support weight loss.

This isn’t to say that you can’t lose weight while training for a half marathon or marathon.

However, prioritizing your nutritional needs for distance running with a balanced diet that will provide ample energy for your training sessions and post-run recovery is not always the same nutrition plan that aids weight loss.

What Is The Best Nutrition For Running?

Nutrition for runners isn’t significantly different from nutrition for overall health. Distance runners need a balance of all three macronutrients (protein, fat, and carbohydrates) along with micronutrients (vitamins and minerals) and water.

However, long-distance running, such as longer runs and high-intensity speed workouts, burns a lot of calories, so training for a half marathon, marathon, or even 10k distance usually requires more carbs and protein than non-runners, and attention needs to be paid to nutrition timing relative to training runs.

Here is a brief overview of the macros for running nutrition:

Carbs

Carbohydrates are the body’s preferred fuel source during high-intensity workouts. Even long runs and race pace efforts are predominantly fueled with carbohydrates as the energy source.³Hawley, J. A., & Leckey, J. J. (2015). Carbohydrate Dependence during Prolonged, Intense Endurance Exercise. Sports Medicine, 45(S1), 5–12. https://doi.org/10.1007/s40279-015-0400-1

‌The storage form of carbohydrates in the body is glycogen, which is predominantly stored in the muscles and liver. 

Pre-workout meals and snacks that are rich in carbohydrates help ensure glycogen stores are optimized for longer runs and high-intensity workouts so that you have a ready supply of glucose as the energy source for your muscles.

Here are some of the best carbs for runners:

• Vegetables: Spinach, kale, artichokes, arugula, Swiss chard, Brussels sprouts, broccoli, zucchini, cucumbers, onions, cauliflower, radishes, mushrooms, peppers, cabbage, celery, asparagus, yellow squash, cucumbers, beet greens, onions, etc.
• Starchy veggies: Sweet potatoes, white potatoes, winter squash, peas, corn, cassava, beets, turnips, parsnips, carrots, yams, pumpkin (technically a fruit).
• Fruits: Apples, bananas, pears, peaches, oranges, grapefruit, berries, cherries, pineapple, kiwi, plums, mangos, star fruit, grapes, nectarines, papaya, melon, guava, clementines, pomegranates, apricots, figs, etc.
• Whole Grains: Whole oats, whole wheat, quinoa, buckwheat, rye, barley, brown rice, quinoa, teff, farro, arameth, pasta, whole grain bread or bagel, oatmeal, muesli, healthy cereals, etc.
• Legumes: Beans, peas, lentils, peanuts, soy, etc.
• Running-Specific Sports Performance Food: Energy bars, energy gels, sports drinks, dried fruit, chews with glucose and electrolytes (sodium, potassium, calcium, magnesium), etc.

Protein

Protein is essential for muscle repair and to help refuel glycogen stores⁴Protein Supplementation During or Following a Marathon Run Influences Post-Exercise Recovery. (2018). Nutrients, 10(3), 333. https://doi.org/10.3390/nu10030333 after longer runs where glycogen storage can deplete.⁵Stearns, R. L., Emmanuel, H., Volek, J. S., & Casa, D. J. (2010). Effects of Ingesting Protein in Combination With Carbohydrate During Exercise on Endurance Performance: A Systematic Review With Meta-Analysis. Journal of Strength and Conditioning Research, 24(8), 2192–2202. https://doi.org/10.1519/jsc.0b013e3181ddfacf

‌Protein also plays a critical role in numerous physiological functions, such as catalyzing biochemical reactions, forming components of cells and tissues, and building and repairing muscle.  

Protein rich foods to include in your running nutrition plan include:

• Lean Meat: Lean beef, pork, venison, bison, etc.
• Fish: Halibut, salmon, sardines, mackerel, tuna, bass, tilapia, cod, etc.
• Seafood: Scallops, crab, shrimp, lobster, mussels, squid, clams, etc. 
• Poultry: Turkey, chicken, duck, quail, etc. 
• Legumes: Beans, peas, lentils, chickpeas, etc.
• Soy/tofu
• Low-Fat Dairy: Low-fat milk, chocolate milk, cheese, yogurt, cottage cheese, kefir, buttermilk, etc. 
• Eggs

Fat

Healthy fats provide energy and help your body absorb the fat-soluble vitamins, which are vitamins A, E, D, and K. 

Fats also provide a sustainable energy source for fueling your muscles during easy runs and low-intensity workouts.

Healthy fats include:

• Seeds: Squash seeds, chia seeds, flax seeds, pumpkin seeds, sesame seeds, hemp seeds, sunflower seeds, etc. (Also a decent source of protein.)
• Nuts and Nut butter: Almonds, macadamia nuts, pistachios, Brazil nuts, kola nuts, walnuts, cashews, pecans, peanut butter, etc. (Also a decent source of protein.)
• Healthy Oils: Olive oil, flaxseed oil, coconut oil, avocado oil, etc.
• Coconut
• Avocados

How Should I Balance My Macros For Running Performance?

Some of the most common questions that runners have are: What are the ideal macros for marathon training, or what are the ideal macros for running? 

These questions essentially point to determining the right composition of macronutrients in your diet.

Macronutrients are often referred to as macros, so you might see sports nutrition information discussing “macros for running.”

A balanced diet includes all three major macronutrients, carbohydrates, proteins, and healthy fats.

There isn’t a single correct “macros for marathon training” or macro split for runners that will necessarily help every runner feel properly fueled, as it depends on your own training, body weight goals, body size, and overall health.

Most sports nutritionists and registered dietitians who work with endurance athletes, such as runners training for a half marathon or long distance running events suggest the following macros for running:

Each gram of fat contains 9 calories, while carbohydrates and protein each provide 4 calories per gram. 

You can figure out how many calories you want to eat per day using an energy expenditure and BMR calculator or working with a registered dietitian. 

From there, you can calculate how many grams of carbohydrates per day, how many grams of fat per day, and how many grams of protein per day you want to eat to meet your desired macronutrient ratios in your running nutrition plan. 

For example, let’s say you are following a 2,000-calorie diet for your running diet plan.

You decide that you want to use the following macros for marathon training:

• 60% of your calories from carbs
• 20% of your calories from protein
• 20% of your calories from fat

Then, you multiply your macros from marathon training by the number of calories in each macronutrient.

• Carbs: 2000×.60 = 1200 calories per day. Then, because there are 4 calories in each gram of carbohydrates, you divide 1200 by 4 to get 300 grams of carbohydrates per day.
• Protein: 2000×.20 = 400 calories per day. 400/4 = 100 grams of protein per day
• Healthy fats: 2000×.20 = 400 calories per day. 400/9 = 44 grams of fat per day

Note that this would be a high-carb diet plan for marathon training and likely does not provide enough calories for marathon training (unless the runner has a very low body weight and petite body size), but should serve as an illustration of how to determine macros for marathon training and the number of grams of protein, carbohydrates, and fats to eat per day.

Runners who are training for shorter distances, such as a 5K, 10K, or even half marathon, would probably be in the 50 to 55% for carbohydrates.

In addition to getting enough of each of the macronutrients in your running nutrition plan, it is also important to ensure that you are getting all of the essential micronutrients.

Micronutrients are typically found in nutrient-dense foods such as vegetables, fruits, nuts, seeds, legumes, low-fat dairy products, eggs, tofu, lean protein, and fatty fish.

This is why eating a balanced diet with a variety of food groups is so critical in order to prevent nutritional deficiencies. 

Moreover, the “best runner’s diet plan“ will include a variety of foods from each of these food groups. 

For example, you shouldn’t have apples every day as your only fruit or rely just on carrots and cucumbers for your vegetables. 

Rather, you want to aim to have at least 30 different foods per week, particularly focusing on including a wide range of fruits and vegetables of different colors. 

This will help provide different micronutrients and phytochemicals. These antioxidants will help fight inflammation from your training and provide a good mix of vitamins and minerals.

Do Runners Need To Take Supplements?

Some long-distance runners (half marathon, marathon runners, and ultrarunners in particular) may also need to take supplements to support their nutrient needs.

Supplements for long-distance runners are particularly important in cases where the runner is unable to follow a balanced diet due to food allergies, or if a specific type of diet is followed, that is known to be deficient in certain micronutrients.

For example, I am a vegan runner, so when I am training for a half marathon or trying to do a marathon training plan, it becomes all the more important to take supplements of certain key micronutrients.

For my needs, these supplements include omega-3 fatty acids, vitamin B12, iron, calcium, and vitamin D because the vegan diet is deficient in these fatty acids, vitamins, and minerals.

Supplements of macronutrients like protein powder or omega-3 fatty acids can also be helpful for runners who have trouble meeting their caloric needs, follow a restrictive diet, need to increase body weight, or need the convenience of protein powder or protein bars for post-run nutritional needs.

Electrolytes and sports drinks can also be helpful for long distance runs and hard workouts where you are sweating a lot.

Sports drinks and drinks with electrolytes like sodium, potassium, magnesium, and calcium, serve double duty by helping with hydration and preventing electrolyte depletion. 

If the sports drinks have glucose or other simple sugars, these supplements can also help serve as a fuel source for your carbohydrate intake in your pre-run or in-run fueling.

For distance runners who struggle with eating enough solid food before running and during long distance runs—particularly for half marathon or marathon training—drinking sports drinks with glucose and electrolytes is one of the simplest ways to help meet the carbohydrate intake you need.

Rather than having to rely on energy gels or whole food sources of glucose/carbohydrates while running, sports drinks can be a great alternative.

That said, sports drinks alone generally will not provide enough glucose for runs that are longer than 90 minutes.

Energy gels or other forms of simple carbs such as dried fruit, energy chews, bananas, applesauce, maple syrup, or honey packets can be used as a fuel source during long runs and on race day.

What Are The Hydration Needs For Runners?

In addition to food, runners need to think about hydration.

Drink enough water throughout the day so that your urine is light yellow.

Pre-run hydration and rehydrating after running are critical to running performance and preventing dehydration. 

Water with electrolytes or sports drinks is preferred for longer distance workouts that exceed 60 minutes or so, particularly if you are sweating a lot or doing a morning run where you haven’t had much of a pre-run meal.

Otherwise, plain water is fine. 

If you are going to be taking in energy gels, energy chews, dried fruit, or other fuel sources during a workout, you can also drink plain water without needing to supplement it with electrolytes and glucose.

Overall, a runner’s diet needs to focus on performance nutrition (fueling before, during, and right after your workouts) and your daily diet.

Following a balanced diet outside of the window of training runs is the best way to ensure that your body is getting the nutrients you need to support overall health, training, recovery, and a healthy body weight.

If you have any concerns about your nutritional needs or the best foods to eat as a runner, you should work with a registered dietitian.

If you would like some more information on carbohydrates for runners, click here.

References

• 1
  Basal Metabolic Rate (BMR) Calculator. (2012). ACTIVE.com. https://www.active.com/fitness/calculators/bmr
• 2
  Body Weight Planner | NIDDK. (n.d.). Www.niddk.nih.gov. https://www.niddk.nih.gov/bwp
• 3
  Hawley, J. A., & Leckey, J. J. (2015). Carbohydrate Dependence during Prolonged, Intense Endurance Exercise. Sports Medicine, 45(S1), 5–12. https://doi.org/10.1007/s40279-015-0400-1
• 4
  Protein Supplementation During or Following a Marathon Run Influences Post-Exercise Recovery. (2018). Nutrients, 10(3), 333. https://doi.org/10.3390/nu10030333
• 5
  Stearns, R. L., Emmanuel, H., Volek, J. S., & Casa, D. J. (2010). Effects of Ingesting Protein in Combination With Carbohydrate During Exercise on Endurance Performance: A Systematic Review With Meta-Analysis. Journal of Strength and Conditioning Research, 24(8), 2192–2202. https://doi.org/10.1519/jsc.0b013e3181ddfacf