4 Things Sports Nutritionists Want Runners to Know

Lauren Bedosky
by Lauren Bedosky
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4 Things Sports Nutritionists Want Runners to Know

Running and nutrition go hand-in-hand.

But don’t think you need to overhaul your nutrition the second you start running or training for a race; minor changes can make a big difference. “It doesn’t matter if you’re a professional or recreational athlete, anyone can see a benefit from fine-tuning their nutrition,” says Jen Sommer-Dirks, RDN, a certified specialist in sports dietetics based in Denver, Colorado.

Among other improvements, small nutritional tweaks — like boosting your carb intake or avoiding slow-digesting foods too close to your run — may limit run-related fatigue and quicken recovery.

Here’s what one sports nutritionist wants runners to know:



According to Sommer-Dirks, many people train for a race to lose weight, but make the mistake of slashing calories too low. “There’s this myth about racing weight, and that lower is always better, but that’s not always true,” she says. “You have to be careful to make sure you’re not restricting your calories too much or that can negatively affect your performance.”

What’s more, those calories often come from carbs, Sommer-Dirks adds. Of the three macronutrients (protein, fat, carbohydrates), it’s especially important to get the right amount of carbohydrates to fuel your runs.

How many carbs you need varies according to your performance and physique goals, as well as your level of activity, but at least 50% of your daily calories should come from carbs, according to Sommer-Dirks. She also recommends tracking your foods for a few days to make sure you’re getting enough.

There’s nothing wrong with running for weight loss, but if you’re training for a race, prioritize getting enough calories and carbs. “You can’t really work on performance and weight loss at the same time, you have to prioritize one over the other,” Sommer-Dirks says.

Even if you’re running for weight loss, make sure you don’t cut your calories too low — 200–300 calories maximum, Sommer-Dirks says.



On the flip-side, some runners eat too many calories, because they assume they’re burning more calories than they really are.

“People start training for a marathon and they actually gain weight, and I think it’s because they think, ‘Oh, running burned so many calories, I could eat what I want,’ but that’s not actually a helpful attitude,” Sommer-Dirks says.

In fact, a study in the Journal of Sports Medicine and Physical Fitness reveals people overestimated the number of calories they burned during a treadmill run by four times. As a result, they ate 2–3 times their actual caloric expenditure at a buffet meal post-workout.

So, while it’s important to get enough calories — especially if you have a performance goal — you should be careful not to overshoot your calories either or assume you burned enough to justify 600 calories worth of doughnuts. It’s not that foods like doughnuts, pizza and chips are necessarily bad, but moderation is key. “It’s OK to have that stuff in moderation, but you want to make sure you’re fueling yourself with fruits and veggies, whole-grain carbs, lean proteins, healthy fats as the basis of your diet,” Sommer-Dirks says.



Not everyone feels like eating after a hard workout, but if you want to get the most benefits from your run, it’s important to refuel with the nutrients (primarily carbs and protein) your body needs to recover and adapt.

Sommer-Dirks recommends getting your recovery meal or snack in your system within 30–45 minutes of finishing a hard workout. During this time, your muscles and other tissues are especially receptive to nutrients — especially carbs.

If you’re not due for a meal immediately after your run, go for an easy recovery snack like a protein shake with fruit, a peanut butter and jelly sandwich with a banana or granola with yogurt and fruit.



Sports drinks can be a great option for replenishing carbs and electrolytes during long and intense workouts beyond 90 minutes, but sipping a sports drink during a short or easy run can add unnecessary carbs and calories to your diet. “If [your run is] less than an hour, your body has enough carbs stored, so you don’t need it,” Sommer-Dirks says. In fact, if you’re running for weight loss, those extra carbs and calories can stall — or even reverse — your results. “Unless you’re running for longer than an hour, water is enough,” Sommer-Dirks says.

About the Author

Lauren Bedosky
Lauren Bedosky

Lauren is a freelance fitness writer who specializes in covering running and strength training topics. She writes for a variety of national publications, including Men’s HealthRunner’s WorldSHAPE and Women’s Running. She lives in Brooklyn Park, Minnesota, with her husband and their three dogs.


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