Physical activity behaviors in school-aged children: Part I.

The purpose of the present study was to integrate and test the utility of two models for explaining and predicting physical activity intentions and behavior--the theory of planned behavior (TPB) and self-efficacy theory. A total of 645 (male = 347) New Zealand children between the ages of 11 and 13 completed demographic information and measures corresponding to the integrated model. One week later, children completed a self-report questionnaire in which they were asked about their physical activity behaviors in the previous week. Two hierarchical regression analyses were conducted to predict goal intention and physical activity behavior, respectively. Results showed that the constructs of the TPB (attitude, subjective norm, perceived behavioral control [PBC]) significantly predicted goal intention (p < .001) in Step 1, explaining 57.3% of the variance. Task and barrier efficacy also contributed significantly to the prediction (R² = .01, p < .001) when entered in Step 2. When all variables were considered together--attitude, β = .15, p < .001; subjective norm, β = .29, p < .001; PBC, β = .37, p < .001; task efficacy, β = .12, p < .01; and barrier efficacy, β = .02, p > .05--only barrier efficacy did not predict goal intention. With regard to physical activity behavior, goal intention was entered in Step 1 and was a significant predictor (p < .001), accounting for 13.5% of the variance. Step 2 revealed that PBC contributed significantly to the prediction of behavior (R² = .01, p < .01), and the inclusion of task and barrier efficacy in Step 3 also resulted in a significant increase in the amount of explained variance (R² = .16, p < .001). When all variables were considered together--goal intention, β = .12, p < .05; PBC, β = .03, p > .05; task efficacy, β = .16, p < .01; and barrier efficacy, β = .35, p < .001--task and barrier efficacy emerged as the two strongest predictors of physical activity behavior. Future research should examine the utility of task and barrier efficacy in predicting objectively measured physical activity behaviors in children. [ABSTRACT FROM AUTHOR]