Effectiveness of exercise training after bariatric surgery-a systematic literature review and meta-analysis

We aimed to conduct a systematic review and meta-analysis of controlled trials assessing exercise training programs in patients with obesity undergoing bariatric surgery. We systematically searched exercise training studies performed after bariatric surgery published up to June 2017. Studies reporting changes in body composition, physical fitness, functional capacity, objectively measured physical activity, quality of life or relevant health outcomes were included. The review protocol is available from PROSPERO (CRD42017069380). Meta-analyses were conducted using random-effects models when data were available from at least five articles. Twenty articles were included, describing 16 exercise training programs, of which 15 were included in the meta-analysis. Overall, exercise training was associated with higher weight loss (mean difference: -2.4 kg, 95% CI: -4.2; -0.6, I²  = 49%, n = 12), higher fat mass loss (-2.7 kg, 95% CI: -4.5; -1.0, I²  = 50%, n = 8) and improved VO₂ max and functional walking (standardized mean difference: 0.86, 95% CI: 0.29; 1.44, I²  = 57%, n = 6; 1.45, 95% CI: 0.32; 2.58, I²  = 89%, n = 6, respectively). Exercise training was not associated with lean body mass changes. In conclusion, exercise training programs performed after bariatric surgery were found effective to optimize weight loss and fat mass loss and to improve physical fitness, although no additional effect on lean body mass loss was found.