FRIDAY, May 6 (HealthDay News) -- Americans walked and biked a bit more in 2009 than they did eight years earlier, new research finds.

But the increases were minor, especially for cycling, according to the report published online May 5 in the American Journal of Public Health.

For the study, researchers analyzed data from the 2001 and 2009 U.S. National Household Travel Surveys and found that the average American made 17 more walking trips in 2009 than in 2001, covering nine more miles each year, and made two more bike trips covering five more miles.

The prevalence of "any walking" among Americans remained the same, although the percentage of those who walked at least 30 minutes daily increased slightly from 7.2 percent in 2001 to 8 percent in 2009.

In addition, the study found that the prevalence of "any cycling" among Americans remained at 1.7 percent, and the percentage of those who did at least 30 minutes of cycling daily remained at just under 1 percent.

Walking and cycling increased among men, the middle aged, employed, well-educated and people without cars, but decreased among women, children and seniors. This suggests that social inequities play a role in discouraging "active travel," the researchers noted in a news release from the American Public Health Association.

"In designing the right mix of policies, it is important to target women, children and seniors, who are the most vulnerable pedestrians and cyclists and require special attention to protect them from the dangers of motor vehicle traffic," John Pucher, of Rutgers University in New Brunswick, N.J., and colleagues wrote.

"Improved infrastructure for walking and cycling should be combined with educational and promotional programs to help encourage the necessary behavior change toward a more active lifestyle," the researchers concluded.

More information

The American Podiatric Medical Association has more about walking.