Group-based physical activity interventions for postpartum women with children aged 0-5 years old: a systematic review of randomized controlled trials.

Background: It is estimated that less than one third of women (28%) worldwide, are not sufficiently active, and there is evidence indicating physical activity (PA) participation is lower during pregnancy and the postpartum period. Despite the importance of educating and encouraging postpartum women to engage in PA, existing systematic reviews have only focused on examining the impact of individually tailored PA interventions and on specific postpartum populations such as women who are inactive (i.e., do not meet PA recommendations) or women at risk of gestational diabetes mellitus or postnatal depression. This review aims to fill this gap by examining the impact of group-based PA interventions on postpartum women's PA levels or other health behavior outcomes.

Methods: A systematic literature search was conducted using four electronic databases (MEDLINE, CINAHL, EMBASE and PsychInfo) of published studies between 1st January 2000 and 31st October 2020. Studies were included if they targeted postpartum women with no current health conditions, had children aged 0-5 years, and engaged postpartum women in a group-based PA program that reported PA or other health behavior outcomes. Out of a total of 1091 articles that were initially identified, six were included.

Results: Group-based PA interventions were moderately successful in changing or increasing postpartum women's self-reported PA levels and psychological wellbeing in the first 2 years of their offspring's life. Overall, group-based PA interventions were not successful in changing or increasing postpartum women's objectively measured PA levels, but only one study objectively measured postpartum women's PA levels. Narrative synthesis highlights the heterogeneity of the outcomes and methodologies used, and the low to medium risk of bias in the included studies.

Conclusion: To strengthen the evidence-base for group-based PA programs with postpartum women there is an on-going need for more rigorous randomised controlled trials of appropriate length (at least 3 months in duration) with an adequate dose of group-based PA sessions per week (to meet PA guidelines), and that utilise objective measures of PA. In addition, future PA interventions for this population should include, at the very least, fidelity and process data to capture the characteristics or design features that appeal most to postpartum women.