As healthy, active individuals, runners need carbohydrates to have a place at the table. Carbs are essential nutrients that provide our bodies with the energy we need to fuel day-to-day activities, and they’re the driving force behind our run workouts. But unfortunately, they’ve been pegged as something to cut back on or avoid altogether.
It’s true that not all carbs are created equal. Studies have shown eating too many refined carbs—anything made with white flour—can lead to an increased risk for type 2 diabetes, as well as heart disease and stroke. But that doesn’t mean you need to cut this important macronutrient completely out of your diet.
Instead, focus on finding the best carbs to eat. Read on to find out why carbs are an important part of a healthy diet, how runners can effectively use them to fuel workouts, and the best carbs for runners.
Why are carbs important for runners?
Carbohydrates are our bodies’ primary source of energy, especially for your working muscles. And while our bodies can rely on fat and protein for energy too, these two macronutrients take a lot longer to digest than carbohydrates. This can be problematic if you’re looking for an immediate source of energy to fuel your run.
“Our bodies are always using fat and carbohydrate for energy. It’s never one or the other,” Megan Robinson, registered dietitian, C.S.S.D, and certified level 1 RRCA run coach tells Runner’s World. On slow recovery runs, Robinson says, your body will rely more on fat than carbohydrates for energy. But for more intense workouts—think speedwork, interval sessions, tempo runs, or even long-distance runs—your body will need more energy, faster.
“Anytime you’re doing a longer run (longer than 90 minutes) typically, your body will start to burn through glycogen. So, if you want to sustain pace, or you want to sustain energy without hitting the wall or bonking, you have to replenish muscle glycogen through carbohydrate,” Robinson says. If not, your glycogen stores deplete, translating to a decrease in performance—less stamina, less drive, and a faster “bonk.”
Plus, if there’s no readily available energy, you will start to break down muscle tissue, meaning all that hard work you put into building muscle in the gym kind of goes out the window. “If you really do too many runs fasted, or you do too many runs without carbohydrate—especially on the longer runs—you’re reducing your energy availability and your body, in the long run, will start to break down your muscle for energy,” Robinson says.
Eating an adequate amount of carbohydrates throughout you day at the appropriate times is key to maintain your energy levels and keeping your performance on par. Robinson says having the right amount of carbs either before or during a workout—depending on the level of intensity—will also help you maintain your blood sugar levels. This blood sugar control also impacts your alertness and ability to continue a workout. (Your brain works on carbohydrates, too!)
What are the best carbs for runners?
The best carbs to eat to fuel daily activities and workouts will be whole grains, fruits, and vegetables. But, Robinson says, it’s tricky because not all carbs are bad and even refined grains—when eaten in moderation—have a place in our diets.
“We’re not going to be eating whole wheat pasta, or a fibre carb bar in a training session because they’re going to wreak havoc on our gut,” Robinson says. “So during training, we want to stick to the simple carbs or the refined carbohydrates, because those are the quick-acting carbs that get into our bloodstream fast and that is what is more easily digested when we’re exercising.”
But bottom line when it comes to the best carbs to eat: It’s all about finding a balance between what you eat, how much you eat, and when you eat it.
Try to increase your portion sizes of carbohydrates and decrease your protein and fat intake in the meal you eat prior to running, Robinson says. For example, at breakfast, if you typically have a Greek yoghurt with fruit, swap the yoghurt for one cup of cooked oatmeal. For a postrun meal, bring it back to a balance with a mix of carbs, proteins, and fats.
A general rule of thumb, Robinson says, is maintaining a 3:1 carb-to-protein ratio. This looks like half a plate of leafy green salad with one-third avocado, two eggs scrambled, and a medium-sized baked sweet potato.
There are lots of really healthy, nutrient-rich foods out there that would make the list of best carbs for runners. But here are a few top choices:
- Sweet potato (and other starchy vegetables, such as squashes)
- Whole grains (rolled oats, farro, whole grain brown rice, quinoa, millet, rolled oats)
- Sprouted breads
- Fruits (banana pre-workout, berries post-workout)
- Dried fruit (limit to pre-workouts due to high-sugar content)
How many carbohydrates should you be eating every day?
The portion of carbohydrate on your plate is going to depend on your intensity, duration of run, and timing of your meals. Robinson says, if you’re doing a light activity or exercising during your off season, you will need about 3 grams of carbohydrate for every kilogram of bodyweight.
For those of us who are casual runners (not pushing paces or doing hard workouts multiple times a week), the portions you need are not much more than non-runners. So you can stick to eating a diet that consists of about 10 to 35 precent of your total daily calories coming from protein, 45 to 65 percent from carbs and 20 to 35 percent from fats, as recommended by the USDA Dietary Guidelines for Americans.
As for runners training for races, you should consume about 5 to 6 grams of carbs per kilogram of bodyweight. Robinson says eating less than 200 grams of carbs a day is a red flag because most runners who are training for a marathon or any race should be consuming at least that amount or more.
How do carbohydrates affect weight loss?
No matter the scenario, the scoop is that cutting a food group completely out of the diet is unrealistic for healthy, sustainable weight loss. That’s especially true for runners who literally run-on carbohydrates—but also for anyone looking to maintain their energy and focus.
Instead, your plan of attack for weight should be about choosing better quality carbohydrates (think whole foods, fruits, and veggies, rather than items like chips or cookies). And focus on making small changes rather than doing a diet overhaul.