What to Eat Before, During, and After Exercise
An interview with sports dietitian Christine Rosenbloom.
Is it bad to exercise on an empty stomach, especially in the morning?
It really depends on the type of exercise -- a brisk walk or light jog on an empty stomach is fine; just drink a glass of water before heading out the door. For more intense exercise, eat some easy-to-digest carbs (a packet of instant grits, a slice of toast, half a plain bagel, a banana, or cup of fruit cocktail washed down with a glass of water) to help provide fuel. After sleeping, the overnight fast can deplete your liver stores of carbohydrate, so a quick boost of carbs before longer exercise is recommended.
Can eating a high-protein diet help bulk up muscles?
The only way to bulk up muscles is to hit the gym and perform progressive resistance exercises. Protein can help provide the raw material to build muscle, but the protein has to be pulled into muscles through exercise. Aim to eat a small amount of protein (10-20 grams, or about 2-3 ounces of lean meat, 2 cups of low-fat milk, or a scoop of most protein powders) after each bout of weight training to give your muscles the needed building blocks.
Why do you need to eat protein or drink protein shakes after exercising?
Muscles need protein for recovery and growth, and the best time to deliver protein appears to be right after exercise. Providing high-quality protein after exercise gives your muscles the fuel and the building blocks needed for both repair and for growth.
Protein shakes and powders carry a certain allure, but your muscles don’t care if the protein comes from a hard-boiled egg, glass of chocolate milk or whey protein shake. Whatever you choose, more isn’t better -- only 10 to 20 grams of protein is needed to provide amino acids (the building blocks of protein) to muscles.
With so many sports drinks, bars, and more to choose from, how do you make the best choices?
A good sports drink contains 14-15 grams of carbohydrate in 8 ounces. It should also contain about 110 milligrams of sodium and 30 milligrams of potassium in the same volume. But if you are exercising to lose weight, stick to water or a "lighter" version of sports drinks with fewer carbs and calories.
Look for energy bars that contain about 5 grams of protein, with some carbohydrate (preferably with more naturally occurring sugars) and very little fat. Many energy bars are just glorified, expensive candy bars, so remember that "energy" means calories and watch out for high-calorie bars. They are helpful for athletes on the go, so if you can't eat before a long tennis match, an energy bar can help.
Choose protein powders made from whey protein or milk proteins (milk protein contains two types of proteins, both whey and casein). Use them within 30 minutes after exercising to provide needed amino acids to muscles. For weight gain, use a protein drink as an evening snack.