RAND Study Finds Neighborhood Parks Associated with More Physical Activity in Adolescent Girls

Adolescent girls who live within one-half mile of a public park are significantly more physically active than other girls, according to a RAND Corporation study issued today.

In the wake of growing national concern about increasing rates of obesity and health problems brought about by Americans' diets and sedentary lifestyles, the study findings could have implications for both males and females in other age groups as well, said Deborah A. Cohen, a senior natural scientist at RAND and lead author of the study.

“Neighborhood and community parks are strongly associated with physical activity,” Cohen said. “If girls become more active when they live close to a public park, further research may show the same thing happening to others in a neighborhood.”

The RAND Health study appears in the November issue of the journal Pediatrics and is titled “Public Parks and Physical Activity Among Adolescent Girls.” RAND is a nonprofit research organization.

Park proximity is particularly important for adolescents, who are usually too young to drive. Cohen said the study found that physical activity increased somewhat for girls within a mile of parks and showed the greatest increase among girls who lived less than one-half mile from a park.

“It could be that just having a park in the neighborhood creates a setting where physical activity is normal part of daily life,” Cohen said. “The more we see others being active, the more likely we are to have higher expectations about physical activity and to be more physically active ourselves.”

Using baseline data from the Trial of Activity for Adolescent Girls — a national research study focusing on middle school girls — the RAND study examined the physical activity of 1,556 girls in the sixth grade in six cities. It also counted the average number of public parks within a half-mile radius of the homes of girls in the cities.

The sites and the number of parks in the half-mile radius of the girls' homes are:

• Minneapolis, Minn. (2.2 parks)
• Baltimore, Md./Washington, D.C. (1.8 parks)
• San Diego, Calif. (1.2 parks)
• New Orleans La. (0.9 parks)
• Columbia, S.C. (0.7 parks)
• Tucson, Ariz. (0.34 parks)

The girls studied by RAND were fitted with accelerometers — devices that measure intensity of movement — and were monitored for six days for activity ranging from brisk walking to running.

On average, the researchers found that girls only got about 114 minutes a week of intense physical activity outside of school hours, or about 16 minutes a day.

“The U.S. surgeon general recommends that all children and adolescents get at least 60 minutes of exercise a day, so we still have a long way to go in encouraging girls to be active,” Cohen said.

The study also found that parks with “active” amenities — such as basketball courts, playgrounds and walking paths — were associated with more physical activity than parks with “passive” amenities, such as picnic areas and lawn games. Girls were less active if the nearby parks had skateboarding facilities, which Cohen attributed to skateboarding being more popular with males than females.

“Boys are using them, and girls stay away,” Cohen said. “The implications are that while special facilities are good, they may benefit one group to the exclusion of another.”

The study suggests that communities should make parks a higher priority, particularly ones with amenities like running tracks or walking paths, which also are relatively inexpensive to create.

Previous studies have shown that girls become less physically active once they reach adolescence, and that girls are generally less physically active than boys.

Despite the 1972 passage of Title IX, the comprehensive federal law that prohibits sex discrimination against students and employees of educational institutions, girls tend to play fewer sports than boys.

In earlier studies in Los Angeles, researchers observed that the number of males using parks was 40 percent higher than the number of females, and males were twice as likely to be engaged in vigorous physical activity.

Cohen would like to see future research track adolescent girls' physical activity in more detail to learn where the girls exercise most often.

Other authors of the study include: J. Scott Ashwood, Molly M. Scott and Adrian Overton, of RAND; Kelly R. Evenson and Diane Catellier of the University of North Carolina at Chapel Hill; Lisa Staten of the College of Public Health at the University of Arizona; Dwayne Porter of the University of South Carolina; and Thomas L. McKenzie of San Diego State University.

The study was funded by a grant from the National Institutes of Health/National Heart, Lung, and Blood Institute.

RAND Health is the nation’s largest independent health policy research program, with a broad research portfolio that focuses on health care quality, costs and delivery, among other topics.