Predictors of physical activity after bariatric surgery - the role of self-regulation abilities

Abstract

Background: Physical activity is an essential component of a healthy lifestyle, however the impact of physical activity following bariatric surgery remains unclear. This study aimed at identifying demographic, anthropometric and self-regulatory predictors of post-bariatric physical activity. Methods: Measures of weight, age, sex, education, intention, planning, self-efficacy and action control were taken one year after surgery in a prospective cohort of 230 patients undergoing Roux-en-Y Gastric Bypass. 1.5-2 years postoperatively, 133 (57.8%) participants wore an ActiGraph GT3X accelerometer for seven consecutive days. The final sample consisted of 112 (48.6%) participants with valid accelerometer recordings (mean age 46.8 years (SD 9.3), 81.3% women). Patients were recommended to be physically active of moderate to vigorous intensity (MVPA) for at least 150 min/week. Findings: Mean BMI before and one year after surgery was 44.8 kg/m2 (SD=5.5) and 30.6 kg/m2 (SD=5.0), respectively. Total weight loss was 28.9% (SD=7.5). 17.9% of the participants were considered sufficiently active (MVPA). As intention, planning, self-efficacy and action control were highly inter-correlated, a principal component analysis was conducted, suggesting one underlying factor (Eigenvalue =10.2, accounting for 57% variance) labelled ‘self-regulation abilities’. Multiple regression analysis showed that being single, having higher education and greater self-regulatory abilities predicted postoperative physical activity, explaining 24% of the variance. Weight loss was not associated with post-surgical activity. Conclusions: Targeting patients’ self-regulation ability may be a mean for improving physical activity after bariatric surgery. Considering the high inter-correlations between the self-regulation scales, further examination of self-regulation measures in the context of bariatric surgery is warranted.