Change in physical activity participation among adolescent girls from 8th to 12th grade.

BACKGROUND Physical activity levels of girls decline in adolescence, but little is known about changes in participation in specific types of physical activity. This study examined change in participation in specific activities during adolescence in girls. METHODS Girls (N = 398, age 13.6 +/- 0.6 y at baseline, 58.5% African American) from 31 middle and 24 high schools in South Carolina completed the 3-Day Physical Activity Recall (3DPAR) in 8th, 9th, and 12th grades. Girls reported their predominant activity and its intensity level in each 30-min time block on the previous 3 d. RESULTS Vigorous physical activity declined from 45.4% in 8th grade to 34.1% in 12th grade. The probability of participating in several forms of vigorous physical activity in 12th grade was strongly associated with participation in those activities in 8th grade. CONCLUSION Early-in-life participation in sports and other forms of vigorous physical activity are important to the maintenance of physical activity during adolescence in girls.