Smartphone app-based interventions targeting physical activity for weight management: A meta-analysis of randomized controlled trials

Background: Being overweight and obese are major public health challenges worldwide. Smartphone apps are an innovative platform to deliver physical activity modifications for weight management. This study aimed to ex-plore the efficacy of smartphone app-based interventions targeting physical activity for obesity-related outcomes and compare the efficacy among behavioral change techniques. Methods: Five online databases were searched for randomized controlled trials in September 30, 2021. Hedges' g was used to compute effect sizes. The random effect models were conducted for all analyses. Results: In total, 12 trials were selected for qualitative and quantitative syntheses. Smartphone app-based inter-ventions exerted small-to-moderate effects on body weight, body mass index, and body fat percentage. The meta-regression found that the older age of participants and a longer duration of the intervention increased the effect. Subgroup analyses found that the interventions were more effective on body weight among partici-pants with a disease or disability, and on body mass index in participants who were obese or overweight. Apps with features such as reminders, self-reporting, and a health coach used as behavioral change techniques were more effective. Conclusion: Smartphone apps are an effective and feasible strategy for physical activity modification using behav-ioral change techniques. Smartphone app-based interventions can promote physical activity for weight manage-ment. (c) 2022 Elsevier Ltd. All rights reserved.