Brisk walking avoids obesity

Men and women who walk or ride a bike to work appear more fit, and men are less likely to be overweight or obese and have healthier triglyceride levels, blood pressure and insulin levels, according to a report in the July 13 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.

For most adults, 60 minutes of brisk walking per day is sufficient to meet physical activity guidelines for avoiding weight gain, according to background information in the article. "One potentially effective means of increasing physical activity is through alternative, non-leisure forms of physical activity such as active commuting (walking or biking to work)," the authors write. However, little previous research has been conduced on the cardiovascular and overall health benefits of such lifestyle exercise.

Penny Gordon-Larsen, Ph.D., of the School of Public Health, University of North Carolina at Chapel Hill, and colleagues studied 2,364 adults in the Coronary Artery Risk Development in Young Adults (CARDIA) study who worked outside the home. At examinations conducted between 2005 and 2006, participants reported the length of their commute in minutes and miles, including details on the percentage of the trip taken by car, public transportation, walking or bicycling. The participants' height, weight and other health variables, including blood pressure and fitness levels as assessed by a treadmill test, also were collected. In addition, they wore an accelerometer to measure their levels of physical activity during at least four days of the study period.

A total of 16.7 percent of the participants used any means of active commuting to reach their workplace. "Active commuting was positively associated with fitness in men and women and inversely associated with body mass index, obesity, triglyceride levels, blood pressure and insulin level in men," the authors write.

The results add to existing evidence that walking or biking to work is beneficial, they note. "Public support for policies that encourage active commuting has been shown, particularly for individuals with experience using active commuting and with positive attitudes toward walking and biking," the authors write. "Furthermore, increasing active commuting will have the dual benefits of increasing population health and in reduction of greenhouse gas emissions. Environmental supports for commuting, such as physical environment and sociocultural factors, have been shown to promote active forms of commuting."

Additional research is needed to elucidate other potential benefits of active commuting, as well as unraveling the association between walking or biking to work and other health-promoting behaviors, they conclude.