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.