Poor Surgery (RNY) Not Helped Much by Exercise
The current study demonstrates that a 12-week exercise program after RNY or a Band type bariatric surgery failed to improve most research outcomes, but physical fitness was superior in the exercise group vs the control group.
You want good weight loss = You need a good weight loss surgery
Moderately Intense Exercise Improves Fitness in Most Bariatric Surgery Patients CME
Clinical Context
Bariatric surgery has been demonstrated to substantially reduce weight among obese adults, and it can cure chronic illnesses such as type 2 diabetes mellitus and hypertension. However, the long-term outcomes of bariatric surgery may not reflect the fantastic improvements documented in the short term. A study by Sjöström and colleagues, which was published in the December 23, 2004, issue of The New England Journal of Medicine, examined patients 10 years after bariatric surgery. They found that although surgery promoted excellent weight loss from 0 to 2 years postoperatively, postsurgical patients gained a higher percentage of body weight between 2 and 10 years after surgery vs obese control patients. However, recovery rates from diabetes, hypertension, and hypertriglyceridemia remained superior in the surgery group vs the control group at 10 years.
Institution of exercise programs after bariatric surgery may help promote more sustained weight loss. The current randomized trial by Garg and colleagues examines outcomes of a postsurgical exercise training program.
Study Synopsis and Perspective
Rigorous exercise may be feasible and beneficial to maintain weight after bariatric surgery, according to the results of a randomized controlled trial reported online July 7 in Obesity.
“[W]e didn’t know until now whether morbidly obese bariatric surgery patients could physically meet this goal,” said senior author Abhimanyu Garg, chief of nutrition and metabolic diseases at University of Texas Southwestern Medical Center at Dallas, in a news release. “Our study shows that most bariatric surgery patients can perform large amounts of exercise and improve their physical fitness levels. By the end of the 12 weeks, more than half the study participants were able to burn an additional 2,000 calories a week through exercise and 82 percent surpassed the 1,500-calorie mark.”
The investigators studied the tolerability and efficacy of high-volume exercise program (HVEP) in 33 obese, postbariatric-surgery patients who had undergone Roux-en-Y gastric bypass and gastric banding. Mean body mass index (BMI) was 41 ± 6 kg/m2. Participants were assigned for 12 weeks to an HVEP (n = 21) or to a control group (n = 12). All participants were advised to limit energy intake, and the HVEP group was also counseled to take part in moderate-intensity exercise resulting in energy expenditure of at least 2000 kcal/week. Repeated measures analysis allowed determination of treatment effect.
In the HVEP group, more than half (53%) of participants expended at least 2000 kcal/week during the last 4 weeks of the study, and 82% expended at least 1500 kcal/week. Compared with the control group, the HVEP group had significant improvement at 12 weeks in 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 (group-by-week effect: P = .009 – .03).
“We found that participants in the exercise group increased their daily step count from about 4,500 to nearly 10,000 so we know that they weren’t reducing their physical activity levels at other times of the day,” Dr. Garg said. “We also found that while all participants lost an average of 10 pounds, those in the exercise group became more aerobically fit.”
Some quality-of-life scales improved significantly in both groups. The groups did not differ significantly in changes in weight, energy and macronutrient intake, resting energy expenditure, fasting lipids and glucose, and fasting and postprandial insulin concentrations.
“HVEP is feasible in about 50% of the patients and enhances physical fitness and reduces postprandial blood glucose in bariatric surgery patients,” the study authors write.
Limitations of this study include short duration, small sample size, dropout rate higher in the control group vs the HVEP group, dietary and exercise counseling provided at an individual level and not at the group level, and use of an unsealed pedometer to measure physical activity.
“Whether a HVEP helps to maintain weight loss and improvement in comorbidities in these patients remains to be evaluated in long-term studies,” the study authors conclude. “The studies also need to assess how exercise over the long term affects factors that influence energy balance including energy intake, nonexercise activity levels, body composition, metabolic rate, and gastrointestinal hormones related to satiety and hunger.”
Obesity. Published online July 7, 2011.
Study Highlights
- All study patients had received either Roux-en-Y bypass or gastric banding surgery within 3 months of study enrollment, and all had a baseline BMI of 35.5 kg/m2 or more. Study participants were between the ages of 18 and 65 years, and they exercised less than 20 minutes per day during the previous 3 months.
- Participants were randomly assigned to an exercise group or to a control group. The goal for the exercise group was to expend at least 2000 kcal/week in moderate-intensity aerobic exercise at 60% to 70% of maximal oxygen consumption. Exercise was increased gradually to achieve this goal, and participants were asked to exercise at least 5 times per week. Exercise was partially supervised during 1 to 2 sessions per week.
- The control group did not receive specific exercise instructions.
- Both treatment groups received similar recommendations regarding diet, with recommended calorie restrictions of 1200 to 1500 kcal/day.
- Participants in the exercise group received behavioral therapy regarding exercise and diet, whereas control participants received behavioral therapy regarding diet alone.
- The study interventions lasted 12 weeks.
- The main study outcome was physical fitness, as measured by maximal oxygen consumption on exercise testing. Researchers also measured total physical activity levels and resting energy expenditure, and they followed body weight as well as body composition using dual-energy x-ray absorptiometry. Finally, researchers measured multiple metabolic variables and participants’ quality of life.
- 21 patients were randomly assigned to the exercise group, and 12 patients comprised the control group. The mean age of participants was approximately 50 years, and the mean BMI was 41 kg/m2. More than 90% of participants were women.
- 4 participants dropped out of the control group, as did 5 participants in the exercise group.
- During the last 4-week period of the study intervention, 53% of participants in the exercise group expended at least 2000 kcal/week, and 82% expended at least 1500 kcal/week. The mean number of steps daily in the exercise group increased from 5500 at baseline to nearly 10,000 at 12 weeks.
- The time spent in exercise increased 3 times vs baseline levels in the exercise group but remained stable in the control group.
- The maximal oxygen consumption during exercise (adjusted for body weight) increased by 10% in the exercise group but decreased very slightly in the control group.
- Resting energy expenditure was similar in the exercise and control groups.
- Participants in the exercise group experienced a more significant increase in total caloric intake between weeks 6 and 12 of the study.
- Body weight, waist circumference, and hip circumference declined to similar degrees in the exercise and control groups, and there was a small and similar decline in percent total body fat in both groups.
- The 2 treatment groups were also similar in fasting as well as in postprandial serum insulin and glucose levels. However, the mean incremental area under the curve postprandial glucose response was lower in the exercise group vs the control group.
- Serum lipid and blood pressure values were also similar in comparing the exercise group vs the placebo group.
- Quality of life improved at 12 weeks in the 2 treatment groups to a similar degree.
Clinical Implications
- A previous study suggested that early weight loss after bariatric surgery might not be effectively sustained at 10 years. However, recovery rates from diabetes, hypertension, and hypertriglyceridemia remained superior in the surgery group vs the control group at 10 years.
- The current study demonstrates that a 12-week exercise program after bariatric surgery failed to improve most research outcomes, but physical fitness was superior in the exercise group vs the control group.
The Mini-Gastric Bypass (MGB) 