Before you exercise
A lot of exercisers assume that working out on an empty stomach forces your body to turn to more stored body fat as a source of immediate energy. But in reality, you actually won’t shed any significant weight by trying this trick. In fact, not having enough fuel in your tank may leave you feeling lightheaded as you exercise. Another disadvantage is that it can also prevent you from having the energy and muscle strength needed to really push yourself during your workout. The less drive you have, the less calories you’ll end up burning in each and every session.
Eating too much before you exercise can also backfire on you. After you consume a big meal, your body immediately spends a certain amount of energy trying to digest all those calories. If you try to exercise afterwards, you’ll have less energy to bring to your workout, and, you could also increase your risk of experiencing indigestion, nausea, and vomiting.
Your Best Bet: Eating a small pre-workout snack that contains mostly carbohydrates—and a little protein—two hours of exercising will give you just enough energy to perform at your best (without upsetting your stomach).
Here are some great options that I enjoy: A slice of wheat bread with a tablespoon of peanut butter and a cup of fat-free milk, a cup of plain low fat yogurt with a tablespoon of raisins and 6 almonds, or my favorite: one serving of rolled oats with ground flax seeds, walnuts, and one high-antioxidant fruit (such as a handful of strawberries, or, a kiwi).
After you exercise
While you’re busy sweating through your workout, your body is busy burning through its’ surplus of glycogen—the limited supply of stored carbohydrates your body turns to for energy as you exercise. Once you’ve finished your workout, your body immediately begins to rebuild its’ glycogen supply so it’s ready for whatever new challenge you have for it later.
That’s why it’s important to eat something right after you finish working out, even if your goal for exercise is to lose weight. The reason: If there isn’t any food in your stomach to convert into glycogen, your body begins converting anything it can find into glycogen to replace that energy—starting with your muscles!
Your Best Bet: Eat a non-fat, high-carbohydrate snack immediately after you exercise. Why right away? Your body actually converts food into glycogen at twice the speed within the first 15 to 30 minutes after exercise, so the sooner you snack, the faster you’ll refill your glycogen (so you’re guaranteed to have plenty of energy for your next workout).
Some easy options can include a piece of fruit, an energy drink, or my personal favorite—a power smoothie. Try this recipe: grab a blender and toss in one tablespoon of plain, nonfat yogurt; one scoop of protein powder; a handful of blueberries; one tablespoon of natural peanut butter; a splash of coconut water, and finally, a handful of ice.
Find our full collection of Fitness Foods for more pre- and post-workout recipes.