Strategies for Burning Fat
Q. I do intervals on the stationary bike, pedaling for 30 seconds as hard as I can and then easing up for 30 seconds, and so on. My trainer says interval training "sets your body up to burn more fat." Is this true?
A. Yes. "It is fairly well documented that the more carbohydrate you burn during exercise, the more fat you'll burn afterward," says Glenn Gaesser, Ph.D., an exercise physiology professor at the University of Virginia and co-author of The Spark (Simon and Schuster, 2001). "Interval training burns glycogen [a form of carbohydrate stored in the liver and the muscles] at a very rapid rate."
High-intensity exercise also increases your body's secretion of growth hormone, which research has linked to increased fat-burning. Still, the extra fat-burning that comes from interval training is modest. "You might burn an extra 40-50 calories during the three to six hours after your workout," Gaesser says.
Gaesser recommends interval training two or three times a week, but not more than that. "The nature of the workout is so hard that it can lead to overtraining," he says. Remember, the best strategy for fat loss is to burn more calories than you consume, regardless of the fuel source used.