Pre- to postoperative changes in physical activity: Report from the Longitudinal Assessment of Bariatric Surgery-2 (LABS-2)

Background: Numerous studies have reported that bariatric surgery patients report more physical activity (PA) after surgery than before; however, the quality of the PA assessment has been questionable. Methods: The Longitudinal Assessment of Bariatric Surgery-2 is a 10-center longitudinal study of adults undergoing bariatric surgery. Of 2458 participants, 455 were given an activity monitor, which records the steps per minute, and an exercise diary before and 1 year after surgery. The mean number of steps/d, active min/d, and high-cadence min/wk were calculated for 310 participants who wore the monitor <10 hr/d for <3 days at both evaluations. Pre- and postoperative PA were compared for differences using the Wilcoxon signed-rank test. Generalized estimating equations were used to identify independent preoperative predictors of postoperative PA. Results: PA increased significantly (P <.0001) from before to after surgery for all PA measures. The median values before and after surgery were 7563 and 8788 steps/d, 309 and 340 active min/d, and 72 and 112 high-cadence min/wk, respectively. However, depending on the PA measure, 24-29% of participants were <5% less active postoperatively than preoperatively. Controlling for surgical procedure, gender, age, and body mass index, more PA preoperatively independently predicted for more PA postoperatively (P <.0001, for all PA measures). Less pain, not having asthma, and the self-report of increasing PA as a weight loss strategy preoperatively also independently predicted for more high-cadence min/wk postoperatively (P <.05). Conclusions: The majority of adults increase their PA level after bariatric surgery. However, most remain insufficiently active, and some become less active. Increasing PA, addressing pain, and treating asthma before surgery might have a positive effect on postoperative PA.