Assumptions can steer physical behavior

According to a study by Kansas State University researcher Katie Heinrich, those who think they need more exercise than experts recommend are more physically active, while those who think they need less don't exercise as much.

Heinrich, a kinesiology assistant professor, along with researchers Jay Maddock from the University of Hawaii and Adrian Bauman from the University of Sydney in Australia, explored the relationship between people's knowledge of guidelines for physical activity and their physical activity behavior. The March edition of the Journal of Physical Activity and Health published the results.

"Instead of simply trying to educate the public about the current physical activity guidelines, it may be more effective to increase people's expectations to encourage them to do more physical activity than they think experts recommend," Heinrich said.

The federal government's 2008 physical activity guidelines call for 300 minutes per week of moderate intensity aerobic activity such as fast walking or 75 minutes per week of vigorous intensity aerobic activity like jogging or running. More than 50 percent of Kansans did not meet the recommendations in 2009.

The guidelines are supposed to educate the public about the minimal amount of physical activity that's necessary for health benefits, but previous studies have been unable to show that knowledge of physical activity guidelines was linked to meeting the guidelines, Heinrich said.

"The guidelines did provide information on the specific amount of physical activity to do, but they didn't always indicate how individuals should attain the recommended amount of activity,” she said. “Understanding the utility of the physical activity guidelines is critical as physical activity rates remain low."

Researchers found that nearly half of Hawaiian adults in a telephone survey knew the correct government recommendations.

"Those who thought they needed more physical activity than recommended by experts for health benefits reported more daily minutes of walking or moderate or vigorous physical activity," Heinrich said. "Participants who thought they needed less physical activity for health benefits than recommended by experts did significantly less walking or moderate and vigorous physical activity."

Provided by Kansas State University