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Active Expert: Nancy Clark RD CSSD

2 Posts tagged with the fueling_during_exercise tag

When you are exercising for more than 60-90 minutes, you want to consume quickly absorbed carbohydrates to keep your blood sugar and energy levels stable throughout your run. Many marathoners are confused about what to eat during long runs. The following tips can help you fuel wisely and avoid from hitting the wall. (Remember that it’s important to experiment with fueling during long training runs to avoid any race-day surprises!)


-- How can you tell when you should eat during long runs? Pay attention to your body’s requests for fuel: mood-change, thoughts about food, reduced energy, tired legs, slower running…


--The amount of carbohydrates needed will vary from person to person (body size, speed, intensity, and training will all effect this), but aim for between 150-300 calories of carbohydrates per hour. This can be from a mix of sports drinks like Gatorade to foods like Gu, candy, or dried fruit.


--Most runners start consuming carbohydrates (sports drink) beginning at 45 minutes to an hour into the race. Breakfast fuels the start of the run.


--If you are a slow runner, vary your food choices to reduce "flavor fatigue" for 4+ hours. It’s easy to get through a half marathon relying only on gels, but it’s difficult to keep that up for twice the time. You’re likely to get “sugared out,” meaning your taste buds or stomach may not tolerate the same food for that many hours. Experiment with a few different options during longer training runs to see what your stomach and GI tract tolerate and what gives your body the most energy.


--Convenience is the big advantage to engineered sports foods such as Gu, Chomps, Sport Beans, and the like. Most come in pre-packaged 100-calorie servings, and they are easy to carry with you. However, real food can work just as well, particularly for slower marathoners who will be pounding the pavement for more than four hours.


Here are some common choices among runners:

-       Raisins,dates, dried cranberries—or any dried fruit

-       Swedish fish, jelly beans, gummy bears, or other chewy candy

-       Pretzels, fig cookies

-       Dried cereal

-       Mini peanut butter and jelly (or honey) sandwiches*

-       Banana*


-       *If you prefer snacks that aren’t convenient to carry in your pocket, ask friends or family to stand along your race-day route at points when you know you will need fuel.


--Gatorade or other sports drinks contribute to your carbohydrate intake. Just pay attention to how much you are consuming so you can adjust your food intake. Diluted fruit juice can work well for some too.


For more information:

Nancy Clark’s Sports Nutrition Guidebook

Food Guide for Marathoners: Tips for Everyday Champions


Co-written with student, blogger and runner Sarah Gold.

3,475 Views 0 Comments Permalink Tags: marathon, nancy_clark, fueling_during_exercise, what_to_eat_during_marathon

Carbs by the grams

Posted by Nancy Clark RD CSSD Mar 16, 2011

This past weekend I attended a state-of-the-art sports nutrition conference sponsored by SCAN, the Sports and Cardiovascular Nutritionists practice group of the American Dietetic Association. I had the pleasure of listening to the top researchers offer their latest sports nutrition news. Here’s what researcher and registered dietitian Louise Burke, PhD, Director of Sports Nutrition at the Australian Institute of Sport, had to say about carbohydrates.



•  Don’t try to calculate a diet according to “percentage of carbohydrates”—such as a diet with 60% of the calories from carbs (a typical recommendation for athletes). Rather, define your daily carbohydrate needs in terms of grams per pound (or kilogram) body weight. The guidelines developed by the International Olympic Committee are:

Low intensity exercise:                      1.5 to 2.5 g Carb/lb        (3-5 g Carb/kg)

Moderate exercise (~1 hour/day):      2.5 to 3 g Carb/lb           (5-7 g Carb/kg

Endurance exercise (1-3 hours/day):  2.5 to 4.5 g Carb/lb       (6-10 g Carb/kg)

Extreme exercise (>4-5 h/day):          3.5 to 5.5 g Carb/lb       (8-12 g Carb/kg)


Hence, if you are a serious athlete who weighs 150 pounds and trains for 2 hours a day, you’d need about 375 to 675 g carbohydrate per day. One grams of carbohydrate offers 4 calories, so this equates to 1,500 to 2,700 calories of carb to fully fuel (and refuel) your muscles. This is more carbohydrate than many endurance athletes tend to consume when eating on the run.


• By hitting your carbohydrate targets, you can restore depleted glycogen stores within 24 to 36 hours post exercise.



* If you will be exercising for less than 45 minutes, you have no need to consume carbs (such as a sports drink) during exercise. What you eat pre-exercise will carry you through the workout.


• If you will be exercising for 1 to 2.5 hours, you should target 30 to 60 grams carbohydrate per hour. Your pre-exercise snack should carry you for the first hour, and then you’ll want to target 120 to 240 calories of carbohydrate per hour thereafter. This equates to 120 to 240 calories from carbohydrate.


• If you will be exercising for more than 2.5 hours, you should target 60 to 90 grams of a variety of carbohydrate per hour (as tolerated). That’s 240 to 360 calories from sports drinks, dried pineapple, gels, gummi bears, and other carbs that taste good and settle well.  Be sure to practice fueling during training, so you know what foods and fluids work well – and what ones don’t!


Fuel wisely and perform well!


For more information:

Nancy Clark's Sports Nutrition Guidebook

1,834 Views 0 Comments Permalink Tags: carbohydrates, nancy_clark, sports_nutrition, scan, fueling_during_exercise

Nancy Clark RD CSSD

Nancy Clark RD CSSD

Member since: Jul 8, 2007

Hi! I specialize in nutrition for exercise, and help active people figure out how to manage food, weight, exercise, energy and enjoyment of eating. Let me know if you have any questions!

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