The pattern of influence of perceived behavioral control upon exercising behavior: an application of Ajzen's theory of planned behavior.

The aim of the present studies was to verify the basic assumptions underlying the theory of planned behavior for the prediction of exercising intentions and behavior among adults of the general population (study 1) and a group of pregnant women (study 2). In both studies, baseline data were collected at home with trained interviewers and with the use of paper-and-pencil questionnaires. The self-report on behavior was obtained 6 months (study 1) and between 8 and 9 months (study 2) after baseline data collection. In study 1, perceived behavioral control influenced behavior only through intention. In study 2, none of the Ajzen model variables was associated to exercising behavior. Nonetheless, intention was influenced by attitude, habit, and perceived behavioral control. The results of the present studies suggest that perceived behavioral control contributes to the understanding of intentions to exercise but not to the prediction of exercising behavior.