What if we told you that you could get all the better-body benefits of a half-hour workout in just 8 minutes? Sound too good to be true? We thought so too, until we talked to the experts.
The secret is supercharged, high-intensity interval training — a shorter but revved-up version of typical interval workouts. In fact, scientists are so excited about these new findings that the American College of Sports Medicine hosted a special session on the topic at its latest conference.
Try one — or all — of our speedy routines, ranging from 8 to 20 minutes. In just 2 weeks, you'll see a fitter, firmer body. Keep it up to flatten your belly, slim your thighs, and even drop a size this month — without dieting.
Why Intervals Slim Faster
Introducing short bouts of vigorous activity can speed up weight loss and cut your workout time by up to half or more. Australian researchers found that women who alternated just 8 seconds of high-intensity exercise with 12 seconds of low-intensity activity for 20 minutes, 3 times a week, slimmed down faster than steady-paced exercisers who worked out twice as long.
Those who did intervals lost up to 16 pounds, shrunk their bellies by 12 percent and their thighs by 15 percent, and gained, on average, 1 ? pounds of metabolism-revving muscle in 4 months — without dieting.Intervals increase calorie burn both during and after exercise, which helps you lose weight faster. They may also work on a biochemical level. Vigorous activity normally produces lactate, a by-product of the breakdown of carbs for energy that inhibits fat burning, says lead author E. Gail Trapp, PhD, exercise science researcher at the University of New South Wales, Australia.
It appears that by doing supershort bouts, lactate production is reduced to blast fat more effectively. At the same time, interval workouts may increase adrenaline, a hormone that helps to burn belly fat.
The Expert: Craig Ballantyne, a Toronto-based exercise physiologist and strength coach who specializes in interval routines, designed the workouts.
Workouts at a Glance
What you'll need: Supportive athletic shoes (specifically running ones if that's what you're doing), watch with a second hand or timer, cardio machine for Workout #2.
What to do: Choose one of our supercharged high-intensity interval workouts — or mix and match them — and perform it 3 times a week on nonconsecutive days.
How to do it: During low-intensity portions, you should be able to easily carry on a conversation. When you kick it into high gear, push yourself to the point that talking is nearly impossible. "Research shows that just about anyone — including people with heart disease, diabetes, or obesity — can safely benefit from vigorous, short bouts," says Martin Gibala, PhD, professor of kinesiology at McMaster University in Ontario. If you have any health conditions or don't exercise regularly, check with your doctor before trying these routines.
For faster results: Add traditional cardio and strength workouts to your schedule.