Let me know the results if you try this workout routine.
While researching a book on exercise and the brain, John Ratey learned that intense exercise releases a hormone that burns belly fat and adds muscle fibers. So the Harvard Medical School psychiatrist swapped out 40-minute jogging sessions on the treadmill for something less time consuming but more vigorous: Twice a week, he now jogs for a total of 20 minutes and includes five exhausting sprints of 20 to 30 seconds apiece. After a month, he was amazed at the results. "I didn't change my diet, and I spent less time on the treadmill," he says. "But all of a sudden, I was 10 pounds lighter."
Many of the people I work with are time starved," says Todd Durkin, a trainer and conditioning coach in San Diego. "They don't have an hour a day to work out."