The availability of local-area commercial physical activity-related facilities and physical activity among adolescents.
BACKGROUND
A significant number of American youth do not participate in sufficient levels of physical activity.


METHODS
This article reports the association between the availability of commercial physical activity-related facilities and self-reported physical activity behavior among United States adolescents. Geographic identifiers at the ZIP-code level were used to combine repeated cross-sections of individual-level data on 8th-, 10th-, and 12th-grade adolescents from the Monitoring the Future (MTF) Survey with external commercial physical activity-related facility outlet density measures obtained from business lists from Dun and Bradstreet for the years 1997 through 2003. The estimation samples based on questions from different survey forms included a total of 195,702 observations on which information on physical activity (sports, athletics, or exercise) was available and 58,876 observations on which information on vigorous exercise behavior was available.


RESULTS
The results showed a statistically significant but very small association between local-area per capita availability of commercial physical activity-related facilities and physical activity behavior among U.S. adolescents. An additional local-area facility per 10,000 capita was associated with only a 0.22 percentage point increase in frequent vigorous exercise among the full sample of adolescents. By gender and grade level, the study found significant associations among female and older students: increasing availability from a low (1 facility) to a high (8 facilities) number of local-area facilities was associated with a 6.6% and 9.0% increase in frequent physical activity and frequent vigorous exercise among 12th-grade girls, respectively, and a 6.4% increase in frequent vigorous exercise among 12th-grade boys.


CONCLUSIONS
Improving the availability of commercial physical activity-related opportunities among underserved populations may help to increase activity levels among older adolescents and girls.
Powell
Lisa M
LM
Department of Economics, University of Illinois at Chicago, Chicago, Illinois 60608, USA. powelll@uic.edu
Chaloupka
Frank J
FJ
Slater
Sandy J
SJ
Johnston
Lloyd D
LD
O'Malley
Patrick M
PM
D000293:Adolescent; D003132:Commerce; D003625:Data Collection; D015444:Exercise; D005260:Female; D020446:Fitness Centers / Q000600:supply & distribution*; D006801:Humans; D008297:Male; D010809:Physical Fitness; D014481:United States