Fitness Plan: Rest to Burn More Fat

July 20, 2007 -- Looking to burn fat through exercise? Resting during your workout may help, Japanese researchers report.

Here's the fat-burning fitness plan they tested: Exercise for 30 minutes, take a 20 minute break, and finish with another 30 minutes of exercise.

That revs up fat metabolism even more than a solid hour of exercise, note the researchers, who included Kazushige Goto, PhD, of the life sciences department at Japan's University of Tokyo.

Goto's team studied seven healthy, physically active men who were 25 years old, on average.

At the researchers' lab, the men pedaled stationary bikes for an hour without taking any breaks.

On another day, they rode the stationary bike for half an hour, sat in a chair and rested for 20 minutes, and then pedaled for 30 more minutes.

For comparison, the men visited the researchers' lab one more time just to rest for an hour, without exercising at all.

The researchers monitored the men's fat metabolism and hormone levels before, during, and after each session. As expected, an hour of pure rest was a dud when it came to fat metabolism, compared with the fat-burning effects of exercise.

But resting during exercise revved up fat metabolism during and after exercise, compared with a solid hour of exercise with no breaks.

The findings, published recently in the Journal of Applied Physiology, may mean that to burn fat, you're better off budgeting a breather into long workouts.

But the study was small, and the men weren't new to exercise, so the researchers plan to test the theory in other groups of people.

Meanwhile, if you're ready to start exercising, check in with your doctor first.

• Visit our Exercise and Fitness message board and ask your questions of WebMD expert Rich Weil, MEd, CDE.