By Sarah Gold, M.S.
Brigham and Women's Hospital
Spring racing season is officially in full swing. And endurance events continue to gain popularity. From half and full marathons to triathlons and century bike rides, endurance races are taking center stage on many athletes' racing calendars.
As the miles increase on your training schedule, it's important to choose the right food and drink for long workouts and race day.
Our muscles can store enough fuel for about 60 to 90 minutes of endurance exercise. For longer workouts, you need to refuel them with carbohydrates from food, drink or a mix of both. Here's what you need to know.
During endurance exercise our bodies rely primarily on glucose (sugar), which comes from carbohydrates. Most endurance athletes need between 100 and 250 calories (25 grams to 60 grams carbohydrates) per hour of exercise longer than 60 to 90 minutes. But the amount depends on:
Your fuel should mostly come from carbohydrates, particularly those low in fiber. Fiber makes it more difficult for your body to absorb the carbohydrates. Also, many athletes get stomach cramps or diarrhea when they eat foods that contain fiber.
Good choices include:
Try different foods during training so you know what will work best on race day.
Sports drinks, such as Gatorade®, count toward your carbohydrate needs as well. However, most provide only 12 to 14 grams of carbohydrate per 8 ounces. So many athletes may find it difficult to meet their fueling needs with only sports drinks.
Sports products (drinks, gels, gummie, jelly beans) have carbohydrates (usually sugar) along with some electrolytes. (Electrolytes are minerals such as sodium, potassium and chloride. They are important for many functions of your body's cells.)
Marketers of the sports products would like you to believe that they are better than foods you would normally eat or snack on. After all they're "chemically engineered" just for the needs of an endurance athlete. However, recent research suggests that food, like raisins, can be just as effective, and a lot less expensive.
For example, researchers from the University of California at Davis looked at the effect of raisins and sports jelly beans on 11 healthy male endurance runners. They ran for 80 minutes then did a 5k time trial. Each runner used a different fuel for each of 3 time trials: 100 calories of raisins, 100 calories of sports jelly beans and water only.
The results, published in the Journal of the International Society of Sports Nutrition in 2012, showed that the raisins were equally effective as the sports jelly beans. And both were better than water alone. None of the runners reported any gastrointestinal upset with the raisins or the sports beans, which is a concern for many runners. Similar results have been reported in cyclists, and with other low-fiber whole food options.
Your body needs electrolytes, like sodium and potassium, for normal muscle contractions and nerve function. Sodium is the main electrolyte you lose when you sweat. The more you sweat, the more sodium you lose.
Thus, on longer training sessions, particularly in the heat of the summer, you may need to add some sodium to your fuel. You can get this from a sports drink (i.e. Gatorade® or homemade with water, juice and salt added), or cereal, pretzels or a peanut butter and jelly sandwich. Many of the sports gels also have some sodium.
Find what works best for you by trying different fuel options during your training sessions.
Many sports products come in 100-calorie packages. This can be convenient. But it can be just as easy to pack some raisins in a snack-sized plastic bag. If you're out training or racing for several hours, you may want to try more than one type of fuel. Just don't try anything new on race day – you never know how your body will respond.
Sarah Gold, M.S. is a dietetic intern at Brigham and Women's Hospital. She graduated with a B.B.A in Marketing from the George Washington University and a M.S in Nutrition Communication from Tufts University Friedman School of Nutrition Science and Policy. She is a distance runner, outdoor cyclist and triathlete.