Dose-Response of Exercise Training following Roux-en-Y gastric bypass surgery: A randomized trial

OBJECTIVE: Roux-en-Y gastric bypass(RYGB) can cause profound weight loss and improve overall cardiometabolic risk factors. Exercise (EX) training following RYGB can provide additional improvements in insulin sensitivity(S(I)) and cardiorespiratory fitness. However, it remains unknown if a specific amount of EX post-RYGB is required to achieve additional benefits. METHODS: We performed a post-hoc analysis of participants who were randomized into either a 6-month structured EX program or a health education control (CON). EX(N=56) were divided into tertiles according to the amount of weekly exercise performed, compared to CON(N=42): Low-EX=54±8; Middle-EX=129±4; High-EX=286±40 minutes per week. RESULTS: The High-EX lost a significantly greater amount of body weight, total fat mass and abdominal deep subcutaneous abdominal fat compared to CON(p<0.005). S(I) improved to a greater extent in both the Middle-EX and High-EX compared to CON(p<0.04). Physical fitness (VO(2)max) significantly improved in the High-EX(+9.3±4.2%) compared to CON(−6.0±2.4%)(p< 0.001). Skeletal muscle mitochondrial state 4(p<0.002) and 3(p<0.04) respiration was significantly higher in the High-EX compared to CON. CONCLUSION: A modest volume of structured exercise provides additional improvements in insulin sensitivity following RYGB, but higher volumes of exercise are required to induce additional weight loss, changes in body composition and improvements in cardiorespiratory fitness and skeletal muscle mitochondrial capacity.