Priority Research Centre in Physical Activity and Nutrition, University of Newcastle, Callaghan, New South Wales, Australia.
Health Educ Behav. 2013 Aug;40(4):415-25. doi: 10.1177/1090198112455642. Epub 2012 Sep 14.
To examine the utility of the theory of planned behavior (TPB) for explaining physical activity (PA) intention and behavior among a large population sample of overweight and obese adolescents (Alberta, Canada), using a web-based survey. Secondary objectives were to examine the mediating effects of the TPB constructs and moderating effects of weight status.
A subsample of 427 overweight and 133 obese participants (n = 560), completed a self-administered web-based questionnaire on health and PA behaviors, including assessment of attitude, subjective norm, perceived behavioral control (PBC), and intention to participate in regular PA. Structural equation models were examined using AMOS 17.0.
Overall, 62% of the variance in intention was accounted for by attitude, subjective norm, and PBC; whereas 44% of the variance in PA behavior was explained by PBC and intention. When examining the TPB separately in overweight and obese subsamples, 66% and 56% of the variance for PA intention was explained for overweight and obese subsamples, respectively; and 38% and 56% of the variance in PA behavior were accounted for in the overweight and obese subsamples. Overall, attitude was the strongest predictor of PA intention, whereas PBC was the strongest predictor for PA behavior. Intention was not predictive of PA behavior.
These results provide partial support for the utility of TPB in explaining PA behavior in a sample of overweight and obese adolescents. In particular, strong associations regarding attitude and PBC were evident across each subsample. These findings have implications for tailoring PA programs in this population.
利用基于网络的调查，检验计划行为理论（TPB）在解释超重和肥胖青少年（加拿大艾伯塔省）大量人群样本中身体活动（PA）意向和行为时的效用。次要目的是检验 TPB 结构的中介效应和体重状况的调节效应。
从超重和肥胖青少年中抽取 427 名（n=427）和 133 名（n=133）参与者作为子样本，完成了一份关于健康和 PA 行为的自我管理网络问卷，包括对态度、主观规范、感知行为控制（PBC）和定期参加 PA 的意向的评估。使用 AMOS 17.0 检验结构方程模型。
总体而言，意向的 62%由态度、主观规范和 PBC 解释；而 PA 行为的 44%由 PBC 和意向解释。当分别在超重和肥胖子样本中检验 TPB 时，超重和肥胖子样本的 PA 意向解释率分别为 66%和 56%；PA 行为的解释率分别为 38%和 56%。总体而言，态度是 PA 意向的最强预测因素，而 PBC 是 PA 行为的最强预测因素。意向不能预测 PA 行为。
这些结果为 TPB 在解释超重和肥胖青少年的 PA 行为方面的效用提供了部分支持。特别是，在每个子样本中，态度和 PBC 之间存在很强的关联。这些发现对针对该人群量身定制 PA 计划具有启示意义。
