Sue Y.S. Kimm|Nancy W. Glynn|Andrea M. Kriska|Shannon L. Fitzgerald|Deborah J. Aaron|Shari L. Similo|Robert P. McMahon|Bruce Barton
Longitudinal changes in physical activity in a biracial cohort during adolescence
report describes development use two selfreport methods objective measure assess longitudinal changes physical activity large biethnic cohort young girls childhood adolescencethe nhlbi growth health study nghs multicenter study obesity development 2379 black white girls followed ages 910 yr 1819 yr nghs years 110 caltrac activity monitor used objectively quantify activity levels years 35 3d diary ad habitual patterns questionnaire haq administered annually biannually respectively subjectively quantify physical activity levels changing pattern activities girls matured 10yr study period necessitated periodic form changes empirical analytic approaches developed help distinguish true longitudinal changes activity levels potential numerical artifacts resulting modifications formsthe longitudinal activity data indicate steep decline level reported activity baseline year 10 indicated ad scores 4468 2921 metmin x d1 35 well haq scores 293 49 mettimes x wk1 83 parallel trend pattern decline activity among two selfreport methods mirrored similar decline using caltrac method physical activity assessment years 3 5 ad decreased 22 whereas haq caltrac declined 21the longitudinal data physical activity collected nghs cohort confirm dramatic decrease overall level physical activity transition childhood adolescence consistency among three methods indicate ad haq useful tools assessment activity levels adolescent girls