Does intrinsic motivation strengthen physical activity habit? Modeling relationships between self-determination, past behaviour, and habit strength

Habit formation is thought to aid maintenance of physical activity, but little research is available into determinants of
habit strength aside from repeated performance. Previous work has shown that intrinsically motivated physical activity, underpinned
by inherent satisfaction derived from activity, is more likely to be sustained. We explored whether this might reflect a tendency
for self-determined activity to become more strongly habitual. A sample of 192 adults aged 18–30 completed measures of motivational
regulation, intention, behaviour, and habit strength. Results showed that self-determined regulation interacted with past
behaviour in predicting habit strength: prior action was more predictive of habit strength among more autonomously motivated
participants. There was an unexpected direct effect of self-determined regulation on habit strength, independently of past
behaviour. Findings offer possible directions for future habit formation work.