How Do You Fuel Your Workout?

Energy bars, fitness drinks, protein powders, sports supplements -- are these the best ways to power your workout? Here's the scoop on which foods can help fuel your fitness efforts.

What should I eat before a workout?

Your body needs fuel for exercise, but eating a large meal right before working out can cause discomfort. To avoid this, wait at least an hour or two after a full meal before exercising. The larger the meal, the longer you should wait. If you haven't eaten in several hours, however, your fuel tank will be on empty. A small snack (such as yogurt, half a bagel, or a piece of fruit) eaten 30 to 60 minutes before exercise will boost flagging blood sugar levels without causing you nausea or indigestion.

Carbohydrate is your body’s preferred fuel, so include whole grains, starchy vegetables, fruit, or nonfat or low-fat dairy products in meals and snacks eaten before a workout. Liquid meals, such as milk and fruit smoothies, are also an option. Avoid high-fat foods, because they slow digestion.

It's important to drink enough water during exercise.

Are energy bars a good choice?

Energy bars are convenient but they're not magical. Their "energy" comes from about 250 calories worth of carbohydrates, fat, and protein. Be cautious of bars that have special ingredients such as ginseng and ginkgo. These won't provide any additional energy boost and may interfere with medications. Choose low-fat bars with no more than 20 grams of protein. A bagel, yogurt, and fruit or fig bars will give you just as much energy and cost less.

Do I need a sports drink?

Not if you are exercising at a light or moderate level for an hour or less. Sports drinks replace fluid lost in sweat and provide carbohydrates for energy. Drink them if your workout is strenuous and lasts more than an hour or if you sweat profusely. Drink two cups of sports drinks or water before and after exercising and small amounts every 15 to 20 minutes during exercise. By the time you are thirsty, you are already somewhat dehydrated.

Will sports supplements give me an edge?

Sports supplements abound, but most have not been proved to boost performance. Creatine has become popularized as a way to improve muscle mass and strength, but most studies do not support the use of creatine to enhance sustained aerobic activities. Amino acids don't appear to build muscle any better than the more balanced protein in food. Skip the protein powders, too. Serious athletes need slightly more protein than others, but most people get plenty of protein from food. Chromium is marketed for weight loss and performance enhancement, but its safety and effectiveness need more investigation.

Bottom line: Whether you're a weekend warrior or a seasoned athlete, your best performance comes from eating a balanced diet and drinking plenty of fluids.