Moderators of the intention-behaviour and perceived behavioural control-behaviour relationships for leisure-time physical activity

Background: Intention is a key determinant of action. However, there is a gap between intention and behavioural performance that remains to be explained. Therefore, the aim of this study was to identify moderators of the intention- behaviour and perceived behavioural control (PBC)behaviour relationships for leisure- time physical activity. Method: This was tested in reference to Ajzen's Theory of Planned Behaviour. A sample of 300 volunteers, 192 women and 108 men, aged 18 to 55, participated in the study. At baseline, the participants completed a self- administrated psychosocial questionnaire assessing Ajzen's theory variables (i. e., intention and perceived behavioural control). The behavioural measure was obtained by mail three months later. Results: Multiple hierarchical regression analyses indicated that age and annual income moderated the intention- behaviour and PBC- behaviour relationships. However, in the final model predicting behaviour (R-2 =.46), only the interaction term of PBC by annual income (beta =.24, p = 0.0003) significantly contributed to the prediction of behaviour along with intention (beta =.49, p = 0.0009) and past behaviour (beta =.44, p < 0.0001). Conclusion: Physical activity promotion programs would benefit not only from focusing on increasing the intention of low intenders, but also from targeting factors that moderate the perceived behavioural control- behaviour relationships.