Couples' daily self-regulation: The Health Action Process Approach at the dyadic level

Abstract

Objective: Regulating health behavior change often occurs in a dyadic context of romantic relationships. Dyadic approaches to standard health behavior change models are, however, barely considered. We investigated volitional processes of the Health Action Process Approach model for two health behaviors within a dyadic context of romantic couples. Specifically, we tested whether day-to-day volitional self-regulation predicted one's own and one's partner's cigarettes smoked (Study 1) and physical activity (Study 2).

Methods: In two dyadic intensive longitudinal studies (Study 1: 83 dual-smoker couples intending to jointly quit smoking; Study 2: 61 overweight couples intending to become physically active), heterosexual partners independently reported on intention, self-efficacy, action planning, and action control in end-of-day diaries. In Study 1, daily number of cigarettes smoked was assessed via self-report. In Study 2, daily moderate-to-vigorous physical activity (MVPA) was assessed objectively via accelerometers. In both studies, dyadic cross-lagged intensive longitudinal analyses based on the Actor-Partner Interdependence Model were applied.

Results: Across both studies, individual's own volitional self-regulation positively predicted one's own health behavior (less cigarettes smoked and more MVPA). One's partner's action control and intention also positively predicted one's own health behavior. A marginal partner effect for self-efficacy was found in the context of smoking only.

Conclusions: Behavioral self-regulation is not only relevant for individuals themselves, but some volitional processes may spill over to their partners. This highlights the need to specify couple-level processes involved in health behavior change, and to consider a social context of self-regulation.

Fig 1. Hypothesized dyadic version of the Health Action Process Approach in couples where one’s own volitional processes predict better own health behavior (actor effects represented with solid lines) and one’s partner’s volitional processes predict better own health behavior (partner effects represented with dashed lines).

Note: The conceptual model is based on the Actor-Partner Interdependence Model (APIM; [24]) depicting two dyad members, Partner A and Partner B, with predictors and outcome for each member. The dyadic models were calculated separately for each volitional predictor.