Correlates of reduced exercise behaviour in depression: the role of motivational and volitional deficits.

Objective: The study aimed at uncovering the correlates of reduced exercise in depressive patients. On the basis of the Health Action Process Approach (Schwarzer, 2011 ), we hypothesised that reduced exercise in depressive patients can be explained by motivational deficits and volitional deficits.

Design: A longitudinal sample of 56 clinically depressive outpatients was compared to a sample of 56 parallelised non-depressive controls.

Main Outcome Measures: Self-reported intention, exercise, and motivational and volitional HAPA variables were measured with self-report questionnaires at baseline and four-week follow-up.

Results: Depressive patients showed a motivational deficit: they had significantly reduced intentions to exercise compared to non-depressive participants, and they suffered from reduced self-efficacy and increased negative outcome expectations. No differences were found with regard to positive outcome expectations. Depressive patients also showed a volitional deficit: depressive high-intenders were less capable of transforming their intention into action than non-depressive high-intenders. They produced less action plans, had less maintenance self-efficacy and were more easily distracted by barriers.

Conclusion: The lower level of exercise among depressive patients is partly due to motivational, partly to volitional deficits. Interventions should be stage-matched and should focus on pessimistic beliefs (negative outcome expectations, self-efficacy) and planning deficits in depression.