Behaviour Change Techniques in Weight Gain Prevention Interventions in Adults of Reproductive Age: Meta-Analysis and Meta-Regression

Weight gain prevention interventions are likely to be more effective with the inclusion of behaviour change techniques. However, evidence on which behaviour change techniques (BCT) are most effective for preventing weight gain and improving lifestyle (diet and physical activity) is limited, especially in reproductive-aged adults. This meta-analysis and meta-regression aimed to identify BCT associated with changes in weight, energy intake and physical activity in reproductive-aged adults. BCT were identified using the BCT Taxonomy (v1) from each intervention. Meta-regression analyses were used to identify BCT associated with change in weight, energy intake and physical activity. Thirty-four articles were included with twenty-nine articles for the meta-analysis. Forty-three of the ninety-three possible BCT listed in the taxonomy were identified in the included studies. Feedback on behaviour and Graded tasks were significantly associated with less weight gain, and Review behaviour goals was significantly associated with lower energy intake. No individual BCT were significantly associated with physical activity. Our analysis provides further evidence for which BCT are most effective in weight gain prevention interventions. The findings support that the use of key BCT within interventions can contribute to successful weight gain prevention in adults of reproductive age.

Making large changes or small changes to prevent weight gain in young adulthood: which is preferred and by whom?

Knowledge of participant treatment preferences can inform decision-making regarding treatment dissemination and future participant adoption. To compare participant perceptions of two evidence-based approaches for weight gain prevention in young adults to identify the intervention with the greatest likelihood of adoption. As part of a randomized trial (Study of Novel Approaches to Weight Gain Prevention [SNAP]; n = 599) testing weight gain prevention interventions in young adults (18–35 years), individuals assigned to self-regulation interventions using either large changes or small changes reported on perceived personal effectiveness and difficulty of treatment over 3 years. Treatment satisfaction at 2-year follow-up was also reported. Pre-randomization, participants believed the large change intervention would be more personally effective than the small change intervention, although they also considered it more complex. Older age, lower body mass index (p = 0.056), and desire to maintain versus lose weight predicted greater perceived effectiveness of the small change relative to large change intervention. Over follow-up, the large change intervention was no longer perceived as more effective, but perceived effectiveness aligned with assigned treatment. The small change intervention was rated as less complex than the large change intervention at 4 months, but not at other follow-ups. At study conclusion, participants were largely satisfied with both treatments; however, in the small change intervention, individuals who were not successful at preventing weight gain were less satisfied than individuals who were successful. The large and small change interventions are both appropriate for dissemination with no clear advantages based on the participant perceptions.

The Relationship of Diet and Physical Activity with Weight Gain and Weight Gain Prevention in Women of Reproductive Age

Reproductive-age women often see increased weight gain, which carries an increased risk of long-term overweight and obesity and adverse maternal and child health outcomes. Supporting women to achieve optimal weight through lifestyle modification (diet and physical activity) is of critical importance to reduce weight gain across key reproductive life-stages (preconception, pregnancy and postpartum). This review comprehensively summarizes the current state of knowledge on the contribution of diet and physical activity to weight gain and weight gain prevention in reproductive-aged women. Suboptimal diets including a higher proportion of discretionary choices or energy intake from fats, added sugars, sweets or processed foods are associated with higher weight gain, whereas increased consumption of core foods including fruits, vegetables and whole grains and engaging in regular physical activity are associated with reduced weight gain in reproductive age women. Diet and physical activity contributing to excessive gestational weight gain are well documented. However, there is limited research assessing diet and physical activity components associated with weight gain during the preconception and postpartum period. This review highlights the need for further research to identify key dietary and physical activity components targeting the critical windows of reproductive life-stages in women to best guide interventions to prevent weight gain.