Changes in physical function and physical activity in patients up to 5 years after bariatric surgery

Bariatric surgery is effective for patients with severe obesity, but relatively little is known about long-term functional outcomes.

To describe physical fitness and activity changes among bariatric surgery patients in a clinical trial of physical activity interventions through 5 years postoperatively.

Large bariatric center in the midwestern United States.

Preoperatively, 6 months, and 5 years after surgery, 42 bariatric surgery patients wore an accelerometer to track activity and completed strength and cardiovascular endurance testing via treadmill, where estimated metabolic equivalents (METs) and ratings of perceived exertion (RPEs) were obtained.

Preoperatively, 25% of patients reported exertion of <3 METs (equivalent to walking 2.5 mi/hr) as an RPE of 16 ("hard to very hard"). This decreased significantly to approximately 5% of patients 6 months and 5 years after surgery. Before surgery, 7.5% achieved ≥6 METs (vigorous activity) at an RPE of 16. This increased significantly to 36.6% at 6 months and 42.1% at 5 years after surgery. Body mass index and age, but no physical activity measure, predicted functional ability over time. The steps/d and exercise bout min/wk increased significantly from before surgery to 6 months postoperatively (4886.5 to 5948.5 steps and 23.8 to 66.6 bout min), but increases were not maintained at 5 years (5677.7 steps and 41.4 bout min). Conversely, moderate to vigorous min/ d increased progressively from before surgery (17.4) to 6 months (32.3) and 5 years (48.1) postoperatively.

Functional abilities of bariatric surgery patients increased postoperatively and were maintained over 5 years. However, treadmill testing suggests that most patients are still unable to perform sustained activities of 6 METs (vigorous) or greater. Research is needed on bariatric patients' long-term function- and intervention- optimizing outcomes.