Rumor: Eating lots of carbs like pasta prior to running is best.
Truth: Only if you run over 90 minutes
Carbohydrates, or carbs, are primarily used to provide energy for the body. Most-likely you’ve heard, “carbo-load prior to exercise”. In truth it’s only good to eat complex carbs, like pasta, when you are going to exercise strenuously for over 90 minutes. Consuming easier forms of energy first is the body’s default and complex carbs are not easy for the body to convert into energy. So if you are planning a 30 minute or 1 hour run, you will typically not burn lots of complex carbs. In other words, the pasta you ate the night before may not give you the boost you’re looking for, but that doesn’t mean you shouldn’t be eating carbs.
Not all carbs are created equal. They are classified into simple or complex. This distinction is based on the molecular structure of the food as well as how easily the food is absorbed into the body. Simple carbohydrates include Fructose (fruit), Lactose (dairy), Glucose/Fructose (honey), and Sucrose (candy). Complex carbohydrates include most starchy foods like pasta, rice, beans, peanuts, potatoes, corn, cereals, and breads. It is recommended to consume between 40-60% of your daily calories from carbs. COMPLEX carbohydrates are better for the body than simple ones. This is because they produce more energy in the long run, often provide vitamins and fiber, in addition to being a great natural energy source for the body. So why wouldn’t we want to carbo-load prior to a run?
Carbo-loading prior to a short run has many risks. To start, if you are not running a long distance over 90 minutes, you will not use those complex carbs to boost your run. Second, unused energy from excessive carbs will be converted into fat. But before you make every run over 90 minutes, remember carbs may not always be your best source of nutrients. While it is recommended that 40-60% of your diet is carbohydrates, if a high carb meal isn’t part of your typical diet it may disrupt your gastrointestinal system. Usually it’s best to eat something you typically have and your body has adjusted to for an early morning run. Lastly, if you carbo-load it can cause a prolonged “full” feeling. Therefore some runners report they are more prone to side cramps during early morning workouts after carbo-loading. The best advice is to try and follow a balanced diet. Don’t eat excessive carbs, but balance your carbs with meat and vegetables, and don’t deviate from your normal patterns too much when prepping for a run. If you would like to learn more information follow the links below which give an in-depth discussion about nutrition, including the federal government’s guidelines. In the meantime, don’t get pressured into carbo-loading. Think before you eat!
Justin Jellin, DPT, ART
Dietary Guidelines for Americans 2010. 7th ed. Rockville, MD: United States Department of Health and Human Services and United States Department of Agriculture; 2010.
Farrell JJ. Digestion and absorption of nutrients and vitamins. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger & Fordtran’s Gastrointestinal and Liver Disease. 9th ed. Philadelphia, PA: Elsevier Saunders; 2010:chap 100.