What Happens When the Party is Over?: Sustaining Physical Activity Behaviors after Intervention Cessation.

Although extensive research suggests that behavior change interventions can improve physical activity (PA) over the course of an intervention, the maintenance of these improvements beyond intervention termination is less clear. The purpose of this study was to determine, through meta-analysis, whether behavior change interventions produce sustained improvements in PA after interventions conclude. Studies were retrieved from a recent (2019) meta-analysis of 224 interventions. Studies that measured PA at baseline, post-intervention, and a follow-up timepoint were included in this updated review. We examined the effects of these interventions in terms of changes in PA from baseline to post-intervention, baseline to follow-up, and post-intervention to follow-up (relative to control groups). We also examined whether the inclusion of theory and behavior change techniques (BCTs) within interventions as well as the length of time between PA assessments moderated these effects. Thirty-nine interventions (17% of interventions from the previous review) from 31 studies were included in the meta-analysis. Significant improvements in PA were found from baseline to follow-up (d = 0.32). In general, these effects resulted from significant increases in PA from baseline to post-intervention (d = 0.46), followed by significant decreases from post-intervention to follow-up (d = -0.18). Effect sizes did not vary between theory-based and no-stated-theory interventions. The positive effects from baseline to post-intervention and negative effects from post-intervention to follow-up were more pronounced as the length of time between assessments increased. In conclusion, behavior change interventions improve PA over the course of the intervention; however, these improvements are generally not sustained after the intervention concludes.