Predicting exercise behaviour in the context of the health action process approach extended with past behaviour frequency and habit : an examination of volitional variables

The aim of the present study was to investigate the prediction of exercise behaviour in a sample of healthy students (N = 148) in the context of the Health Action Process Approach (HAPA). The HAPA distinguishes between a motivational phase and a volitional phase, and the attention of the present study was paid especially to the volitional variables action planning, coping planning and action control serving as mediators between intentions and behaviour. In addition the inclusion of past behaviour frequency and habit in the model was tested. The HAPA was found useful in predicting exercise behaviour explaining 47% of the variance in exercise behaviour. In the volitional phase action control and self-efficacy emerged as the most proximal predictors of exercise behaviour. The inclusion of past behaviour frequency increased the explained variance in exercise behaviour significantly from 47% to 65% and emerged as the strongest predictor of exercise. The results highlight the importance of post-intentional variables in health behaviour change models. The findings from the present study are discussed in relation to development of the HAPA and consequences for interventions promoting exercise behaviour