Exercise Intensity Matters More Than Duration In Keeping Weight Off: Study

Every little bit counts.

That's the message of a new study in the American Journal of Health Promotion, which showed that even a few minutes of brisk physical activity can add up to protect against obesity.

"What we learned is that for preventing weight gain, the intensity of the activity matters more than duration," study researcher Jessie X. Fan, a professor of family and consumer studies at the University of Utah, said in a statement. "This new understanding is important because fewer than 5 percent of American adults today achieve the recommended level of physical activity in a week according to the current physical activity guidelines. Knowing that even short bouts of 'brisk' activity can add up to a positive effect is an encouraging message for promoting better health."

Currently, U.S. adults are recommended to get 150 minutes of moderate to vigorous exercise a week. Using an accelerometer to gauge what this means, this could also be interpreted as getting to 2,020 accelerator counts per minute. In other words, this is the level of vigorous exercise you'd accomplish from walking at three miles per hour.

The study is based on data from the 2,202 women and 2,309 men ages 18 to 64 who were part of the National Health and Nutrition Examination Survey and who wore accelerometers from 2003 to 2006. Researchers found that the study participants fell into one of four categories of exercise intensity: higher-intensity long bouts, higher-intensity short bouts, lower-intensity long bouts and lower-intensity short bouts.

They found that even the people who engaged in the higher-intensity short bouts experienced benefits to their body mass index. For instance, for women, spending an extra minute of high-intensity exertion each day was linked with a .07 decrease in body mass index.

Plus, for every additional minute each day of high-intensity exertion, obesity odds decreased 5 percent for women and 2 percent for men.

Need some ideas for a quick workout? We've got some options for you, whether you have only 10 minutes to spare or even just five.

Clarification: A previous version of this article did not specify that the "brisk exercise" defined in the study was in accelerometer counts per minute; it only said counts per minute. It has been corrected to reflect this change.