Evidence inhibitory self-control moderates effects of habit on complex but not simple health behaviors.

Theoretically, self-control can be considered as both a facilitator of habit development and a moderator of whether behavior occurs habitually. However, debate remains on the contexts in which such relationships are likely to occur. The current study tested whether self-control, conceptualized into inhibitory and initiatory facets, would predict healthy behavior via habits or moderate the habit-behavior relationship, and whether these effects differed across complex (bootcamp attendance N = 69, physical activity in pregnant women N = 115) and simple (flossing N = 254) behaviors. Three independent samples completed measures of self-control and habit, followed by a prospective measure of behavior. Data were fitted to PLS-SEM models. Inhibitory and initiatory self-control predicted habit in all three samples, and habit in turn predicted each health behavior. Inhibitory self-control only moderated the effect of habit in the bootcamp and physical activity samples. Initiatory self-control did not moderate effects in any sample. Findings indicate that both initiatory and inhibitory self-control are associated with habit. Further, as the moderating effect of inhibitory self-control was only present in the complex behavior samples, results suggest the moderating effects of self-control on the habit-behavior relationship may be best represented by the effect of inhibiting competing cues from disrupting automatically activated behavioral sequences.