The steady increase in the prevalence of obesity is reflected in the rising rate of weight loss surgeries, and repeat surgery for weight regain that occurs 1-2 yr post-weight loss surgery (PWLS). PURPOSE: We performed a systematic review of randomized control trials (RCTs) to determine if exercise was associated with attenuation of weight regain in adults PWLS. METHODS: We searched 5 databases with terms related to exercise, weight, weight regain, and weight loss surgery, and found no systematic reviews of exercise interventions ≥1yr PWLS among adults ≥18 yr, nor did we locate professional exercise guidelines for this population. We then performed a search in PubMed for randomized controlled trials (RCTs) involving exercise interventions in adults ≥18 yr PWLS. Other inclusion criteria were RCTs in peer-reviewed journals published in English, that included the frequency, intensity, type and time of the exercise intervention, and a control group receiving usual care consisting of diet and exercise advice. The standardized mean difference effect sizes (d₊) were calculated following random-effects models for body weight lost, and back-converted to the original unit for clinical interpretation. We assessed inconsistencies in d₊ with the I² statistic transformed from the Q statistic. RESULTS: The second search yielded 442 reports, with only 3 RCTs qualifying. Participants (n=132) were mostly white women 46.8±3.9yr, and 13.1±6.7mo PWLS. Interventions were supervised; lasted 40-60min/session, 2-5d/wk for 12-26wk; and involved moderate-to-vigorous intensity, combined aerobic and resistance training, while 1 added flexibility exercises. Compared to usual care, exercise interventions elicited moderate reductions in body weight ≥1yr PWLS (d₊=-0.46, 95%CIs: -1.12, 0.21; -4.1kg) that did not reach significance (p=0.069) with high levels of heterogeneity (I² =62.9%, 95%CIs: 0.0, 89.4). CONCLUSIONS: In a very limited literature, exercise interventions elicited clinically important reductions in weight of ~4kg representing ~4% of baseline weight ≥1yr PWLS. There is an urgent need for professional exercise guidelines and RCTs examining the effects of exercise on weight regain PWLS with larger, more diverse samples.
Supported by the University of Connecticut Center on Excellence in Teaching and Learning