Using the Theory of Planned Behaviour to Predict Exercise Intention in Obese Adults

Abstract

The purpose of this cross-sectional study was to use Ajzen's Theory of Planned Behaviour (TPB) as a theoretical framework for understanding the intention to be physically active among a group of obese individuals. Individuals (n = 96) classified as obese (BMI ≥ 30 kg/m²) completed a self-administered questionnaire assessing intention to be physically active and its theoretically related variables. The TPB explained 66% of the variance in physical activity intentions. Significant independent predictors of intention were perceived behavioural control (ß = .40) and attitude (ß = .36). The consideration of past behaviour (ß = .32) explained an additional 7% of the variance. These findings support the idea that, in designing interventions for obese individuals, nurses should focus on developing skills to overcome barriers to physical activity and on developing a positive attitude towards this behaviour.