Physical activity levels of patients undergoing bariatric surgery in the Longitudinal Assessment of Bariatric Surgery study.

Background: Bariatric surgery candidates' physical activity (PA) level might contribute to the variability of weight loss and body composition changes following bariatric surgery. However, there is little research describing the PA of patients undergoing bariatric surgery to inform PA recommendations in preparation for, and following, surgery. We describe the PA assessment in the Longitudinal Assessment of Bariatric Surgery-2 study at 6 sites in the United States and report preoperative PA level. We also examined the relationships between objectively determined PA level and the patient's body mass index and self-reported purposeful exercise.

Methods: The participants wore an accelerometer and completed a PA diary. Standardized measures of height and weight were obtained.

Results: Of the 757 participants, 20% were sedentary (<5000 steps/d), 34% had low activity (5000-7499 steps/d), 27% were somewhat active (7500-9999 steps/d), 14% were active (10,000-12,499 steps/d), and 6% were highly active (>or=12,500 steps/d). Body mass index was inversely related to the mean number of steps daily and the mean number of steps each minute during the most active 30 minutes of each day. The most commonly reported activities were walking (44%), gardening (11%), playing with children (10%), and stretching (7%). The self-reported minutes of exercise accounted for 2% of the variance in the objectively determined steps.

Conclusion: Patients present for bariatric surgery with a wide range of PA levels, with almost one half categorized as somewhat active or active. Body mass index was inversely related to the total amount and intensity of PA. Few patients reported a regular preoperative exercise regimen, suggesting most PA is accumulated from activities of daily living. Patients' report of daily minutes of walking or exercise might not be a reliable indication of their PA level.