Effectiveness of a Social Cognitive Theory-Guided, Multi-Component mHealth Intervention on Physical Activity Among Young Adults with Overweight or Obesity

This study examined the effects of a social cognitive theory (SCT)-guided, multi-component mobile health (mHealth) intervention on physical activity (PA), body mass index (BMI), and SCT constructs (exercise self-efficacy, social support, outcome expectations, self-regulation) among young adults with overweight or obesity. Sixty participants were recruited via convenience sampling and randomly allocated to one of four groups: (1) social media-only, (2) fitness application (app)-only, (3) combined social media and fitness app, or (4) control; 56 participants (25 males, 31 females; mean age = 21.52 ± 2.61 years) completed the 6-week intervention. PA, BMI, and SCT constructs were assessed at baseline and post-intervention. A repeated measures ANOVA (or a nonparametric alternative) was performed to examine the main and interaction effects of time and group, and Pearson correlation analysis was conducted to explore associations between changes in SCT variables and changes in PA. The multi-component group combining social media and fitness app interventions demonstrated significantly greater improvements in total PA level and moderate-to-vigorous PA time, as well as a marginally significant increase in exercise self-efficacy compared with the control group. Furthermore, changes in exercise self-efficacy were positively associated with changes in PA variables within the intervention groups. This 6-week intervention provides preliminary evidence supporting the potential effectiveness of a theory-driven, multi-component mHealth approach for enhancing PA among young adults with overweight or obesity. Future studies with longer intervention periods and structured follow-up assessments are warranted to confirm its efficacy and sustainability.