Despite internet frenzies and best-selling books claiming the contrary, carbohydrates are still the prime energy food for runners. Simply put, carbs supply the working muscles with the fuel they can burn most efficiently for high-intensity exercise (and all running, even slow running, qualifies as high-intensity exercise). Your body can burn fats in a pinch, and small amounts of protein, but it won’t feel good when it does. And you won’t perform your best.
For proof we need look no further than the best distance runners in the world—the East Africans. Kenyan runners have been extensively studied as science strives to explain their astounding successes. And research into the Kenyan diet has consistently yielded the same result: The Kenyan runners eat a diet that’s astonishingly high in carbohydrates. They get 70 percent or more of their energy from carbs. The typical American, by comparison, gets 50 percent of his or her calories from carbs.
Of course, low-carb and often high-fat diets have become the rage in the US. As have similar regimens with names like the Paleo Diet, the ketogenic diet, and so on. Sugar and high-fructose corn syrup have been particularly vilified.
Well, sure, no one’s arguing for the health benefits of added sugars. Avoid them as much as possible. But don’t be duped by logical fallacies. Just because added sugars are bad, that does not mean that high-fat diets are good.
Quite the opposite. The vast majority of nutrition experts point out that carbohydrates continue to be the dietary mainstay of the world’s healthiest populations—not just the fast Kenyans, but also the long-lived Okinawans of Japan and the thriving elders of Italy, Greece, and other Mediterranean countries.
Fruit, veggies, legumes, and whole grains—that’s the ticket for runners. These foods are super healthy for several key reasons. First, they are low in fat and calories. They help you maintain an optimal weight. Second, they are packed with vitamins, minerals, and antioxidants. Third, many are accompanied by soluble and insoluble fibers that are lacking in manufactured foods. Fiber has several valuable properties. It slows the absorption of sugars from the stomach, lowering the risk of a high-glucose, high-insulin reaction, and it adds fullness to the meal, meaning you will stay satisfied longer and be less tempted by between-meal snacks.
Choose clean carbs: Years ago I used to fill my supermarket cart with so-called convenience foods. I didn’t want to prepare meals at home. I wanted to spend my time training and racing. If a canned or plastic-wrapped food looked reasonably healthy, I reached for it.
Now I have a new supermarket goal. I try to go through checkout with as few processed and precooked foods as possible. I buy whole fruits, whole veggies, and big bunches of kale and lettuce. My grains, beans, nuts, seeds, and eggs are likewise unprocessed, and my Greek yogurt contains no added flavors or sweeteners. Meals take a little longer to prepare, but not much, and I enjoy the time, because I am working with minimally processed foods that are good for me and good for the planet.
Aim for variety: The greater the variety of foods you consume, the healthier your diet is likely to be. We know this because studies of people who consume vitamin and mineral supplements rarely reach the same conclusions as studies of those who eat whole foods containing supposedly identical nutrients. Nature puts more into foods than man can extract and inject into pills.
Eat well, move, and be healthy: Many low-carb eaters avoid carbs in the belief that they lead to insulin resistance, diabetes, and weight gain. Such people follow the old “You are what you eat” dictum. And again, there’s no doubt that too much added sugar is a bad thing in anyone’s diet. However, that doesn’t mean that all carbs are equally bad. An obesity expert friend of mine who has a PhD in exercise science has coined a more nuanced variation on the old catchphrase. He says, “You are what your body does with what you eat.” More simply, you are what you do.
Here’s what this means. If an overweight thirty-five-year-old consumes four slices of greasy cheese pizza, washed down with twenty-four ounces of a sugary soda, yes, he’s going to nudge himself toward diabetes. But the same won’t necessarily hold true for a lean thirty-five-year-old who regularly runs 20 miles a week. This person has tuned his body to deal with an occasional oversupply of fats and carbs.
You can be perfectly healthy without being perfect twenty-four hours a day.