Predicting the physical activity of new parents who participated in a physical activity intervention

Rationale: The demands of early parenthood may limit the pursuit of moderate-to-vigorous intensity physical activity (MVPA); thus, understanding the predictors of MVPA among this population could help build targeted intervention programs. Objective: The purpose of this study was to examine the correlates of MVPA, in the form of constructs subsumed within the theory of planned behavior (TPB) and multi-process action control (M-PAC) framework, among new parents participating in in a couple-based PA promotion randomized trial across a six-month period in the first year after birth. Methods: In total, 264 participants (132 couples) at the two-month point of parenting their first child were enrolled in the trial through advertisements. MVPA, TPB, and M-PAC constructs were assessed via self-report at baseline, and six-week, three-month, and six-month after baseline time-periods. Results: Dyadic path modeling of the TPB showed that intention only predicted MVPA for mothers and PBC did not predict MVPA. Most of the sample had intentions to be physically active, although the extent to which intentions predicted subsequent MVPA was dependent on mothers and fathers reported strength of planning, habits, and exercise identity (M-PAC variables). Intention was subsequently predicted by affective attitude and PBC for mothers and fathers. Conclusions: Interventions targeting affective attitude and perceived behavioral control may assist in improving MVPA intentions of new parents; yet, additional intervention strategies to increase planning, habit, and especially exercise identity seems warranted for many parents to close the gap between intention and PA. The findings highlight the complementary approach of intention formation and intention translation theories among new parents.