Effects of a 6-month physical activity behavioral intervention in patients following metabolic bariatric surgery: a randomized controlled trial

Background: Promoting habitual physical activity (PA) among bariatric patients is crucial for long-term surgery success, yet it poses a significant challenge for healthcare practitioners. Objectives: This randomized controlled trial (RCT) aimed to examine the effectiveness of a theory-based behavioral intervention on PA level in post-metabolic bariatric surgery (MBS) patients. Setting: University Hospital, Israel Methods: Forty-four patients undergoing MBS were randomized to the intervention (n = 22) or control group (n = 22). The intervention group received a 6-month PA counseling program based on self-determination theory (SDT) and the 5 A's framework, while the control group received usual care. PA level and self-efficacy for exercise (SEE) were assessed pre- (baseline, preintervention) and postoperatively (14 and 28 weeks follow-ups). Anthropometrics, physical function, cardiovascular, and biochemical outcomes were measured at all time points. Results: The intervention group showed greater increases in PA levels across time compared to the control group. A significant increase in step counts from baseline to 14 weeks was observed (P = .003). Significant differences favoring the intervention group were observed in self-reported PA changes from baseline to 14- and 28-week follow-ups (P = .020 and P = .024, respectively). Additionally, Physical function, as assessed by the 6-minute walk test (6MWT) and the 5 sit-to-stand (5STS) test, significantly improved in the intervention group throughout the follow-up period (P < .05 for all), However, no between-group differences were observed in SEE, anthropometrics, cardiovascular, or biochemical parameters. Conclusions: A 6-month behavioral intervention post-MBS significantly enhanced patients' PA levels and physical function. Given its theory-based approach and structured protocol, this intervention could be disseminated to support MBS clinicians and centers. Further research with longer follow-up period is warranted to confirm these findings and assess the long-term effects.