Carbohydrates are the food of choice when you need to fuel up before your workout. But not all carbohydrates provide you with the same type of energy. Some carbs give you a burst of energy while others provide a slow, steady stream. The glycemic index, or GI, is a system that ranks how quickly carbs digest and enter your bloodstream for energy. When it comes to fueling up before your workout, low-GI foods may be the better way to go.
The glycemic index rates carbohydrates on a scale from zero to 100 based on how quickly they digest and raise your blood sugar levels. Foods with a low GI, less than 50, tend to take your body longer to digest and cause a small gradual rise in blood sugar, while foods with a high GI, 70 to 100, digest very quickly and cause a rapid increase in blood sugar levels. Examples of low-GI foods include apples, low-fat yogurt, hummus and wheat tortillas, and examples of high-GI foods include white bread, white rice, watermelon and pretzels.
Glycemic Index and Exercise
When it comes to boosting energy levels for your workout, you may be better off with a low-GI meal before you exercise. A 2006 study published in the "International Journal of Sport Nutrition and Exercise Metabolism" investigated the effects of a low-GI meal versus a high-GI meal on endurance in a small group of recreational runners. The study found that when the runners ate a low-GI meal three hours prior to their workout they had better endurance levels than when they consumed the high-GI meal.
Making the right food choices before you work out helps keep blood sugar steady and can determine whether you have a good workout or a so-so workout. Fueling up with a low-GI snack about two to three hours before you exercise can make all the difference. Good pre-workout meal choices include a container of low-fat yogurt and an orange, peanut butter with apple slices and hummus with carrot or celery sticks.
Benefits of Low-GI Eating
Not only do low-GI foods help fuel your workout, but if you make them your primary carbohydrate choice they can also improve your health. Including more low-GI foods in your diet can make it easier for you to control your weight because they help better control hunger by preventing rapid spikes and drops in blood sugar. A low-GI diet may also significantly reduce your risk of developing diabetes. Eating more low-GI foods may also help keep your blood pressure and cholesterol levels low and help reduce your risk of heart disease.
- University of Wisconsin Hospital and Clinics: Glycemic Index
- Harvard Health Publications: Glycemic Index and Glycemic Load for 100+ Foods
- International Journal of Sport Nutrition and Exercise Metabolism: A Low Glycemic Index Meal Before Exercise Improves Endurance Running Capacity in Men
- Runner's World: Are You High?
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