By Rebecca Scritchfield

As a sports nutritionist, I work with people whose workout regimens span a range of activity, from strength training and dance classes to racing in 5Ks and 50 milers.

While there's no question that my clients need tailored recommendations for fueling their activity, it amazes me how many of them don't eat properly before a workout. Even more concerning is the misguided idea among some that avoiding food before workouts is somehow better because it "helps the body burn more fat." False. In this post, I'll shed some light on fueling up for your best workout.

Fact: Your body needs energy to perform.

"If you can't fuel it, you can't do it." My colleague, fellow registered dietitian Leslie Schilling, once mentioned this phrase to me, and it's become my no-nonsense philosophy on fueling all exercise. It's this simple. Cars don't go far without adequate gas. Planes don't fly without jet fuel. Why would our body "machine" operate without food fuel?

Fueling up doesn't necessarily have to occur one hour before a morning workout -- it can take place the night before. Nancy Clark, another fellow dietician and author of "Sports Nutrition Guidebook," says that a bedtime snack can help to fuel a morning workout. I heeded that advice on a recent trip to Chicago when I enjoyed a piece of deep-dish pizza before hitting the sack. When I awoke at the hotel the next morning, I had enough energy to endure an hourlong jog on the Chicago waterfront. I just needed to hydrate. I had a great jog and was ready for a recovery smoothie after a quick shower. Typically, I would not opt for this plan, but I was out of town and it worked for me. When I'm home, I typically fuel up before a workout with 16 ounces of water and some fruit or toast with peanut butter, varying the amount of food depending on the extent of my workout. If you can't seem to make time to fuel up just before a morning workout, consider the bedtime snack option.

Myth: Forgoing food before a workout helps you burn fat.

Some people think that forgoing food before exercise is a smart "fat-burning" strategy. The rationale is that, with no other fuel available, the body has to burn fat. In reality, the body will use whatever energy is available. After an overnight fast, about 80 percent of stored carbohydrates have already been used. When you don't fuel your workout, your body will draw from whatever carbohydrates are left, as well as protein, possibly muscle, and fat to make up the difference.

Don't just take my word for it. Check out what some of my fellow sports dietitians have to say on the matter:

"I help my clients realize that exercising on an empty stomach often means they don't have the energy to put in a really good workout," says Carol Lapin of Houston, Texas. "Since one of the benefits of aerobic exercise is being able to work hard at a high intensity, they could be missing out. Additionally, I tell them that if they end up not getting enough calories in, they could be losing muscle mass."
"As the team dietitian for the Detroit Red Wings, we know when our athletes have not fueled prior to a game as well as when they did not adequately fuel to recover for the next event," says Lisa McDowell "They may be able to make it through a mediocre practice. However, if one of our games extends beyond three periods into overtime then, oftentimes, the victorious team will be the team best fueled in terms of recovery from the day before as well as game-day nutrition. If you want to achieve the best possible workout, it requires planning."
"I always talk about our metabolism as a 'fire,'" says David Talley, wellness coordinator for Indiana University. "...The best way to get a fire going is providing it with fuel," or calories. Talley explains that fueling up before a workout sets one up for more efficient metabolism, which leads to sustained energy and weight loss.

Fact: Before any workout, eat your carbs.

Of all the foods you could have before a workout, prioritize ones rich in carbohydrates, especially if you really want to "amp up" your fat burn. This is the body's preferred energy source during exercise.

Typically, if you have less than 45 minutes before your workout, your body will do best with simple carbohydrates like fruit or fruit juice. However, you may find that you do well with a bowl of plain, steel-cut oats with raisins and cinnamon. It's OK if there is some protein and fat in the pre-workout meal, but neither will raise your blood sugar and give you the energy your body requires for each muscle contraction. Better to swirl a tablespoon of peanut butter in your oatmeal or smear it on a piece of toast with some banana to make sure you get your carbohydrates.

If you exercise later in the day, your earlier meals and snacks will help to fuel your workout. Make sure your lunch has at least one fist-size amount of carbohydrates. For example, include a slice of whole-wheat bread with a salad and some beans. Then, use your afternoon snack as your opportunity for added nutrition. If, for example, you exercise at 6 p.m., then have a snack around 4 p.m. One good option would be a whole-wheat bagel or English muffin topped with hummus and a few veggies like thin cucumber slices, spinach, and tomato. You may even want some fruit as a side.

How much to eat depends on the frequency, intensity, and duration of your workout, among other factors. If you have an hour or less before your workout, a general guideline is to have about 1 gram of carbohydrate for every kilogram of your body weight (divide pounds by 2.2 to determine weight in kilograms). Some fuel is better than no fuel at all. Even if you only ate a banana, its carbs -- 30 grams -- will help. The important thing is to start somewhere and progress to optimal levels of pre-workout nutrition.

Here are some of my recommended pre-workout foods:

• Fruit. Any kind you like works! Blueberries, apples, peaches, pears, or bananas are great. You can even do canned fruits, but be sure they contain no added sugar and are packed in their own juice or light syrup. If you do fruit juice, keep it to a 1-cup serving.

• Hot or cold cereal. If dairy bothers you, try soy milk with your cereal, preferably a bran-based or whole-grain option. If you crave those sugary cereals from childhood, sprinkle on a little sugar, which you will use up during your workout.

• Toast with nut butter or eggs and a side of fruit. Enjoy a whole-wheat bagel or English muffin with some protein -- either one or two eggs or some nut butter. You could use peanut, almond, cashew, or even Nutella -- who doesn't love the idea of some chocolate in the morning? Strawberries and bananas go great with this choice.

• Smoothies. Blend 1 cup of any fruit with some milk or milk alternative and ice for a great snack you can sip while you get on your workout gear.

• Leftovers. Have some quinoa or couscous left over from dinner? Mix in cherries or raisins and cinnamon to turn last night's meal into your pre-workout fuel.

After a few days of properly fueling your body for your workouts, you will feel so much better. You'll exercise harder, and get better performance results.

Hungry for more? Write to eatandrun@usnews.com with your questions, concerns, and feedback.

Rebecca Scritchfield, MA, RD, ACSM Health Fitness Specialist, helps empower people to build healthy lifestyles. A graduate of the Johns Hopkins University, Scritchfield is a Washington, D.C., based registered dietitian and fitness expert who encourages clients to find exercise that feels great, learn to manage stress, and establish lifelong eating skills that balance individual nutrition needs with hunger and pleasure. Visit her blog at: www.rebeccathinks.com.

MORE ON U.S. NEWS AND WORLD REPORT:

Medicare, Social Security Literally Extend Lives

4 Essential Preparations for a Successful Retirement

Variable Annuities: Greed at Work

Earlier on Huff/Post50:

Loading Slideshow...
  • See A Doctor First

    This may seem like a no-brainer, but if you've been idle for a while, it's important to see a doctor before getting active again, says Dr. Alexis Colvin, an orthopedic surgeon at The Mount Sinai Medical Center in New York City. You want to make sure you don't have any pre-existing conditions, such as heart disease, that might present a problem when you start up your new exercise regimen.

  • Start Slowly!

    Getting active too quickly, often with incorrect form, is one of the primary reasons people over 50 find themselves in her office, Colvin says. It's important to slowly build a base level of strength, flexibility and fitness before pushing yourself to, say, sign up for that marathon.

  • Consider Seeking Professional Help

    It's always helpful to have a little direction and support in starting something new. Colvin suggests getting started with a personal trainer or physical therapist to tailor an exercise program to your goals.

  • Get In A 'Pain-Free Zone Of Activity'

    Low-impact activities, such as swimming or using the elliptical, are all good for people who have joint pain, says Dr. Colvin. If it hurts, don't push it!

  • Think Beyond Cardio

    An active lifestyle isn't limited to throwing on some running shoes and hitting the pavement. Dr. Colvin suggests yoga and pilates, which can help with strength and flexibility even if they don't give you the same cardiovascular workout you might get from the treadmill.

  • Think Outside The Box...Or, Should We Say, The Gym

    Colvin also points to the many home exercise videos available, which can be a great alternative for those who would prefer to exercise from the comfort of their living rooms. The one drawback, she says, is potential for injury from using incorrect form, "since there's no one watching you."

  • Consider Cross-Training

    Mix up your routine and <a href="http://sportsmedicine.about.com/od/tipsandtricks/a/Cross_Training.htm" target="_hplink">consider cross-training</a> (adding swimming and biking to a running program) to prevent boredom, avoid repetitive injuries and improve your overall condition. Exercise with friends to add social benefits to the physical and mental advantages of your workout. Recognize your limits, adjust accordingly and enjoy the quality-of-life benefits of an active lifestyle for many years to come.