Abstract MP70: Proof-of-Concept Trial of a Positive Psychology-Based Physical Activity Intervention After Bariatric Surgery: The Gaining Optimism After Weight Loss Surgery (GOALS) Project

Metabolic/bariatric surgery (MBS) is the most effective treatment available for severe obesity, but weight regain is common, increasing risk for cardiometabolic disease. Physical activity (PA) reduces these risks and aids with weight loss maintenance; however, over 90% of adults after MBS do not achieve at least 150 minutes/week of moderate-to-vigorous physical activity (MVPA) when measured objectively. Negative emotional associations with PA are common in this population (e.g., physical pain or injury, weight stigma). Positive psychological interventions are simple exercises shown to increase psychological well-being. The Gaining Optimism After weight Loss Surgery (GOALS) Project aims to target the emotional barriers to PA in adults with recent MBS using a positive psychological approach combined with motivational interviewing and goal-setting for PA. We tested feasibility, acceptability, and pre-post change in PA and psychological, behavioral, and physiological outcomes in a single-arm proof-of-concept trial to refine GOALS and prepare for a future RCT. GOALS included 10 weekly phone calls plus a written manual and a Fitbit to track PA. Each session included a positive psychology exercise, a PA-related topic, and setting a weekly PA goal. Participants were adults with MBS in the past 6-12 months who reported low physical activity. Primary outcomes were feasibility (session completion rates) and acceptability (participant ratings of session ease and utility). Pre-post assessments included physical activity measured with Actigraph GT3X-BT, a 6-minute walk test, BMI, percent body fat and waist circumference, and self-report measures of depression, anxiety, optimism, internalized weight bias, attitudes around physical activity, and post-MBS behavioral adherence. Mixed effects regression models with a random intercept measured change in outcomes including participants with missing data. Effect sizes (Cohen’s d) estimated magnitude of change given low study power. We enrolled 12 participants (58% female, M age 46 years, 67% non-Hispanic white). They completed 8.5/10 intervention sessions on average and gave high ratings ( M between 8.3 and 8.8/10) of ease and utility. There were increases in MVPA equivalent to an additional 17 minutes/day (d=0.61, p=0.09), 6-minute walk test distance (d=1.06, p=0.01) and reductions in BMI (d=0.81, p=0.04), depression (d=1.22, p<0.01), anxiety (d=0.51, p=0.16), and internalized weight bias (d=0.98, p=0.03), and increases in post-MBS adherence (d=1.44, p<0.01). The GOALS intervention demonstrated feasibility, acceptability, and pre-post improvements in PA and psychological well-being in a small proof-of-concept trial. The intervention is now being tested in a pilot RCT compared to a PA education control. If it continues to show similar effects, the intervention could be integrated into post-MBS clinical care to improve outcomes.