Health behavior intentions predict change in perceived capacity, not controllability: A motivational account of perceived behavioral control.

Understanding how control beliefs relate to motivation is central to health psychology, yet whether such beliefs function primarily as antecedents or consequences of motivation remains unclear. Drawing on two national samples from the Theory of Planned Behavior Replication Project (Germany, N = 2060; UK, N = 2054), this research focuses on two different components of perceived behavioral control, perceived capacity (ability, ease) and perceived controllability (external constraint), and examines their temporal relations with intentions to engage in vigorous physical activity. Confirmatory factor analyses supported a two-component structure of control beliefs and demonstrated that intentions and capacity are empirically distinct. In lagged regressions replicated across samples, Time 1 intentions predicted increases in perceived capacity after accounting for prior behavior and controllability, whereas intentions did not uniquely predict changes in perceived controllability. Refining theoretical models of control in health-behavior change, these findings suggest that motivational commitment may selectively shape self-evaluative control beliefs.