Interval Training

Cut your workout in half and still lose weight...

To all the spinners and runners and stair climbers out there -- there's a new message.

Spending more time at the gym may not help as much as this.

Sprinting -- for even just a few seconds at a time could make your workout dramatically more efficient.

Interval training may be a more effective way to lose weight than we ever realized.

"We use interval training to keep it fun but also to increase the intensity without people really paying as much attention to intensity," Kathleen Kennedy, a trainer, said.

It's a mind trick that appears to work.

Researchers at an Australian University found people who rode for 40 minutes at a steady pace - lost an average of two pounds.

While another group that rode just 20 minutes alternating between eight second sprints and 12 seconds of slower riding -- lost an average of six pounds.

Half the time -- triple the results.

"You work harder but I guess you get some recovery time after which makes it easier - or it feels easier to get a good workout," Melissa Burns, a spinning class participant, said.

Scientists still aren't sure exactly why it works -- one theory is the sprints stimulate hormones that regulate fat cells.

If cycling's not your thing - you can get the same effect on an elliptical machine - a stair climber - or a treadmill - just by working short sprints into your routine.

You can incorporate it into almost anything you do - you can jump rope for three minutes at a fast pace and then sit down and rest.

Bursts of energy to battle the bulge.