Weight regain is a problem among many bariatric surgery patients. Whether a high-volume exercise program (HVEP), a strategy to limit weight regain, is feasible in these patients is unknown. The feasibility of an HVEP in obese post-bariatric-surgery patients was determined by randomizing 33 Roux-en-Y gastric bypass (RYGB) and gastric banding (GB) surgery patients with a mean BMI of 41 ± 6 kg/m2 to an HVEP or control group for 12 weeks. The HVEP group was instructed to expend ≥2,000 kcal/week in moderate-intensity exercise. All patients were counseled to limit energy intake. Treatment effect was assessed by repeated measures analysis. During the last 4 weeks of the study, 53% of the HVEP group expended ≥2,000 kcal/week and 82% expended ≥1,500 kcal/week. Step count, reported time spent and energy expended during moderate physical activity, maximal oxygen consumption relative to weight, and incremental area under the postprandial blood glucose curve were significantly improved over 12 weeks in the HVEP group compared to controls (group-by-week effect: P = 0.009–0.03). Both groups reported significant improvement in some quality-of-life scales. Changes in weight, energy and macronutrient intake, resting energy expenditure (REE), fasting lipids and glucose, and fasting and postprandial insulin concentrations were not different between the two groups. HVEP is feasible in about 50% of the patients and enhances physical fitness and reduces postprandial blood glucose in bariatric surgery patients.