title: Determinants of physical activity in middle school children.
abstract: OBJECTIVE
  To evaluate the theory of reasoned action (TRA) and planned behavior (TPB) in predicting moderate-to-vigorous physical activity (MVPA) in sixth-grade youth.
  
  
  METHODS
  One hundred ninety-eight students completed a questionnaire measuring attitudes, subjective norms, perceived behavioral control, and intentions to be active. MVPA was measured using the CSA 7,164 accelerometer.
  
  
  RESULTS
  Although demonstrating an acceptable fit, the TRA and TPB accounted for only a small percentage of the variance in MVPA. In support of the TPB, the addition of control perceptions to the reasoned action model added to the prediction of intentions and MVPA.
  
  
  CONCLUSIONS
  Within our sample of sixth graders, the utility of the TRA or TPB as a framework for activity interventions appears to be limited.
authors.affiliation: School of Human Movement Studies, University of Queensland, Brisbane, Australia. strost@hms.uq.edu.au
authors.forename: Stewart G
authors.initials: SG
authors.lastname: Trost
authors.forename: Ruth
authors.initials: R
authors.lastname: Saunders
authors.forename: Dianne S
authors.initials: DS
authors.lastname: Ward
mesh_terms: D002648:Child; D015444:Exercise / Q000523:psychology*; D005260:Female; D015438:Health Behavior; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D007389:Internal-External Control; D008297:Male; D009042:Motivation; D013022:South Carolina; D013334:Students / Q000523:psychology*