Post-bariatric Surgery

This study aims to evaluate the effect of a 5-week concurrent exercise program (aerobic and resistance training) on muscle quality, body composition, functional response, and quality of life in individuals undergoing bariatric surgery. This is a single-center, prospective, longitudinal, non-randomized controlled clinical trial with two groups: intervention and control. A total of 84 adults aged 18 to 60 years who have undergone sleeve gastrectomy or gastric bypass and have a medical indication for metabolic rehabilitation will be recruited. The intervention group will complete a supervised concurrent exercise program for 5 weeks, consisting of two in-person sessions per week (10 sessions in total), while the control group will continue with usual care without participating in a structured exercise program. All participants will be assessed at two time points: baseline (postoperative week 4) and 7 weeks after baseline (after 5 weeks of intervention and 1 week of rest). The primary outcome will be muscle quality of the rectus femoris assessed by ultrasound (echo intensity). Secondary outcomes will include body composition (bioelectrical impedance analysis), functional performance (one-minute sit-to-stand test), and quality of life (Moorehead-Ardelt II questionnaire). Additionally, adherence to the exercise program in the intervention group will be evaluated as the percentage of attendance to supervised sessions, and its association with the magnitude of changes in outcomes will be analyzed under a dose-response framework. The results are expected to provide clinically relevant evidence on the effectiveness of exercise in the early postoperative period and to support the optimization of metabolic rehabilitation strategies after bariatric surgery.

The purpose of this study is learn the effect of gastric bypass surgery and sleeve gastrectomy on glucose metabolism mediated by neural and hormonal factors initiated after eating.

The overall goal of this project is to understand the mechanisms by which gastric bypass surgery improves glucose metabolism. The central hypothesis guiding this project is that the reconfiguration of intestinal transit with the Roux-en-Y will increase the release of insulinotropic GI hormones, termed incretins that improve insulin secretion and glucose metabolism. The study is divided into three specific aims. 1. To determine the role of incretin hormones on insulin secretion in patients with gastric bypass surgery using intravenous-oral hyperglycemic clamp. 2. To compare incretin effect and glucose tolerance among patient who suffer from hypoglycemia after RYGB and asymptomatic surgical and non-surgical individuals. 3. To quantify the contribution of GLP-1 to incretin effect enhancement following surgery.