Eating before and after physical activity is crucial, says Lona Sandon, assistant professor of clinical nutrition at the University of Texas Southwestern Medical Center in Dallas. Eating 30 to 60 minutes before exercise delays fatigue and results in a more effective workout, says Sandon.
"The muscles need an immediate carbohydrate source to perform at their best. Exercising on an empty stomach will require the body to make energy from stored muscle protein, thus breaking down muscle," Sandon says. "Decreased muscle mass results in a decreased metabolism, which is what we are typically trying to increase with exercise."
Eat something high in carbohydrates and moderate in proteins 60 to 90 minutes following exercise, advises Sandon.
"These nutrients provide calories, as well as repair muscle tissue broken down by exercise," she says.