Runners love numbers: From miles logged to paces hit, Dietary Guidelines for Americans.
You’re probably pretty familiar with serving size: That’s a standard amount of food, like a cup or an ounce, says Katie Kage, R.D., an assistant professor in Nutrition and Dietetics at the University of Northern Colorado and an exercise physiologist.
A Part of Hearst Digital Media based on a 2,000-calorie-per-day diet and are broken down by recommended amounts per day (think: five servings of vegetables, four servings of fruit, six servings of grains, three servings of dairy, and three servings of The Benefits of the Mediterranean Diet) or week (eight to nine servings of poultry, meat, and eggs; two to three servings of fish and other seafood; five servings of nuts, seeds, beans, and legumes). On a nutritional label, you might see a recommended serving size.
But portions are a little different. A “portion” is all about how much food you’re actually eating, explains Kage. For example, the serving size on the Nutrition Facts label for pasta may be three-quarters of a cup, but you end up making a cup and a half to fill a bowl. Unfortunately, there are no easy guidelines to follow when it comes to portion size. “Portion size is extremely flexible and very individualized, and it can look very different from meal to meal,” says Kage. It should be what works best for you—which can take some time to figure out—and can look very different from meal to meal and depending on your activity and goals.
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Here’s where to start: The Dietary Guidelines for Americans recommend that men consume 2,000 to 3,000 calories per day and women consume 1,600 to 2,400 calories per day for adult women (and “endurance athletes are likely going to need more than 2,000 calories a day to fuel their training,” says Davis). The Food and Nutrition Board of the Institutes of Medicine (IOM) recommends people get 45 to 65 percent of their daily calories from carbohydrates, 10 to 35 percent from protein, and 20 to 35 percent from fat.
Portion control is all about how you break down your food intake—based on those dietary recommendations—throughout the day. “Whether you have one massive meal in the morning and one massive meal at night or you prefer six small meals throughout the day, it’s all the same amount of calories and nutrients,” says Rachel Davis, Ph.D., a clinical nutritionist. It’s a term that’s mostly used related to weight loss (as in, restricting your portions), but it affects performance, too.
“Portion control is so important mainly because of gastrointestinal function,” says Davis. “A massive meal is going to be processed differently than a smaller meal.”
Imagine eating a huge lunch just before going out for an afternoon run. “Instead of your blood being pushed toward your digestive tract to help your body digest and process those nutrients, it’s going to your working muscles. That slows down digestion,” she explains.
Health - Injuries 80 Should Runners Take Vitamin D in Winter, which leaves all that food sitting in your stomach while you’re running and may cause nausea, reflux, intestinal cramping, and diarrhea. Not ideal.
Plus, your body can only absorb so much of certain nutrients at once. For example, nutritionists recommend just 20 to 25 grams of protein each time you eat—if you eat more than that, you’ll overload your system, and it will just get rid of the excess protein. That’s why Davis prefers more frequent, smaller meals throughout the day: “It helps you properly balance the amount of nutrients you’re consuming so your body can actually absorb them,” she explains.
At a meal, your portion sizes should break down like this: one to two palm-sized portions of protein; one or two fist-sized portions of veggies; one or two handfuls of carbs; and one or two thumb-sized portions of healthy fats.
If you find yourself regularly eating more than that, there are a few tricks to better control your portions. You can easily swap your large plate for a smaller one—people ate 77 percent more pasta when using a large bowl compared to a medium-sized bowl in a study published in the run first thing in the morning.
Try drinking a glass of water before eating, too; consuming a pint of water before meals resulted in great feelings of fullness and reduced food intake in a study published in the The Best Energy-Dense Foods for Runners. And when it comes to post-run snacks, separate the correct portions into smaller containers—people ate 129 percent more when served from a large container than a small one, according to a research percent decrease in blood flow Appetite.
As a runner, though, improving your portion control is just like your training: It’s all about consistency. For starters, you should be eating (at least something small and carb-focused, like half a banana) before a run. Yes, even if you like to Should You Eat Before a Run or Head Out on Empty! “That’s going to help your stomach during and after the workout and get everything moving,” says Davis.
After a run, though, runners can feel totally different in terms of appetite: You might finish a run absolutely ravenous and want to eat everything in sight, while your workout buddy might not be able to stomach the idea of eating for up to a couple of hours. (Both of those scenarios are totally normal, BTW.) But whether you raid or avoid the kitchen post-workout, it can throw off your meal patterns and lead to over- or under-eating—both of which can affect your performance.
However you feel post-run in terms of hunger, “you immediately want to get some protein and carbs back into your system within 20 to 30 minutes after your run,” says Kage. “A snack is just enough to curb the initial starvation response in those who want to eat everything in sight, while it’s not so much that it overwhelms a more sensitive stomach.”
If you are someone who hates eating post-run, try a smoothie that’s milk- or yogurt-based—sipping over the course of the next 20 to 30 minutes can help the body recover and get the blood flow back to the digestive system.
Of course, diet is super personalized. Figuring out what nutrients work when—and how much is too much or too little—is a bit of a puzzle, says Kage. Just like it might take some time to figure out what shoes give you the most speed and support of what sports bra won’t chafe your armpits, it takes a little bit of trial and error to see what nutrition plan works for you. But when you do dial it in, the effort (and the few emergency bathroom stops) will have been worth it.
