Clinical trial demonstrates exercise following bariatric surgery improves insulin sensitivity

Abstract

nondiabetic patients following RYGB surgery are typically quite modest compared with the presurgery condition (3). Moreover, there appear to be 2 discrete periods of improvement. The first is immediately after surgery, at which time hepatic, but not peripheral, S I improves in response to acute energy restriction (4-6), while greater, protracted weight loss appears to be more strongly associated with improved peripheral S I (7,8). Even with significant weight loss 1 year following RYBG surgery, peripheral S I is still low compared with that of lean metabolically healthy individuals (3,5,6,9).Exercise is considered a cornerstone for obesity treatment, and while it is not generally viewed to cause substantial body weight reduction (10), it can potently improve peripheral S I and glucose control (11-13) and can reduce the risk of T2D and cardiovascular disease (14,15). There is general consensus that even a single session of moderate intensity exercise can induce an improvement in S I (16). There is also evidence that exercise can BACKGROUND. Roux-en-Y gastric bypass (RYGB) surgery causes profound weight loss and improves insulin sensitivity (S I ) in obese patients. Regular exercise can also improve S I in obese individuals; however, it is unknown whether exercise and RYGB surgery-induced weight loss would additively improve S I and other cardiometabolic factors. METHODS.We conducted a single-blind, prospective, randomized trial with 128 men and women who recently underwent RYGB surgery (within 1-3 months). Participants were randomized to either a 6-month semi-supervised moderate exercise protocol (EX, n = 66) or a health education control (CON; n = 62) intervention. Main outcomes measured included S I and glucose effectiveness (S G ), which were determined from an intravenous glucose tolerance test and minimal modeling. Secondary outcomes measured were cardiorespiratory fitness (VO 2 peak) and body composition. Data were analyzed using an intention-to-treat (ITT) and per-protocol (PP) approach to assess the efficacy of the exercise intervention (>120 min of exercise/week).RESULTS. 119 (93%) participants completed the interventions, 95% for CON and 91% for EX. There was a significant decrease in body weight and fat mass for both groups (P < 0.001 for time effect). S I improved in both groups following the intervention (ITT: CON vs. EX; +1.64 vs. +2.24 min -1 /μU/ml, P = 0.18 for Δ, P < 0.001 for time effect). A PP analysis revealed that exercise produced an additive S I improvement (PP: CON vs. EX; +1.57 vs. +2.69 min

Bariatric Surgery Resistance: Using Preoperative Lifestyle Medicine and/or Pharmacology for Metabolic Responsiveness

“…These findings are consistent with data highlighting that moderate intensity aerobic exercise increases insulin sensitivity and glucose effectiveness (i.e. the ability of glucose to facilitate glucose disposal) [75], along with increased VO 2 max and mitochondrial adaptation for fat oxidation during bariatric-induced weight loss [76]. Supervised endurance exercise or educational based programs with resistance exercise can also facilitate greater weight loss, improved muscle strength and increased fitness capacity [75–77], suggesting overall that exercise is an effective therapy to improve metabolic health in surgical patients.…”

“…the ability of glucose to facilitate glucose disposal) [75], along with increased VO 2 max and mitochondrial adaptation for fat oxidation during bariatric-induced weight loss [76]. Supervised endurance exercise or educational based programs with resistance exercise can also facilitate greater weight loss, improved muscle strength and increased fitness capacity [75–77], suggesting overall that exercise is an effective therapy to improve metabolic health in surgical patients. However, despite higher exercise volumes in the general population appearing to relate to improved glucose regulation [13, 78–79] and cardiometabolic health [80], there is a limitation in the existing body of work on the effects of exercise “dose” on cardiometabolic health maintenance over time as well as on the effectiveness of exercise for the prevention of weight regain.…”

Metabolic Flexibility in Health and Disease

“…Increases in skeletal muscle mitochondrial biogenesis, mitochondria content and function have been reported to explain improvements in both insulin sensitivity (Coen et al, 2015a) and increased capacity for fatty acid oxidation (Jong-Yeon et al, 2002). Calorie restriction-induced weight loss also improves insulin sensitivity (Coen et al, 2015b), but in contrast to exercise, does not seem to enhance the capacity of skeletal muscle for fatty acid oxidation (Toledo and Goodpaster, 2013). Remarkably, these lack of improvements in fatty acid oxidation of skeletal muscle mitochondria correspond to the lack of response to weight loss (Coen et al, 2015a), although some studies have shown that calorie restriction increases mitochondrial content (Civitarese et al, 2007) and function (Vijgen et al, 2013).…”

Bariatric and metabolic surgery: a shift in eligibility and success criteria

“…101 As skeletal muscle is the body's largest glucose buffering system, a conserved large muscle mass promotes insulin sensitivity and protects against the metabolic syndrome. [102][103][104] Moreover, FFM, but not fat mass or BMI, is positively associated with self-determined meal size and daily energy intake in humans. 105,106 Thus, a rapid weight loss mainly at the expense of FFM entails the subse quent loss of protective muscle strength and its metabo lic bene fits on the regulation of energy homeo stasis.…”