Objectively Monitored Physical Activity and Sitting Time in Bariatric Patients Pre- and Post-Surgery

Purpose: Sedentary time, or prolonged sitting/lying time, is an emerging risk factor for severe obesity, independent of physical activity (PA). The purpose of this study was to characterize ambulatory PA as well as sitting/lying time using accelerometry before and after bariatric surgery. Material and methods: Seventeen participants (58.5% female) with a mean age of 46.5 ± 10.1 years, and a Body Mass Index (BMI) of 48.8 ± 6.2 kg/m2 scheduled for bariatric surgery were included in the analysis. ActivPAL™ tri-axial accelerometers were attached to the participants' mid-thigh and worn for 24 hours a day for up to seven consecutive days before surgery, and at three, and six months following bariatric surgery. Mean steps, transitions from sitting-to-standing, as well as standing, walking and sitting/lying time per 24 hours were measured. Results: Prior to bariatric surgery, participants spent 18.6 ± 1.5 hours per 24 hours sitting/lying, representing over 75% of their day. Total sitting/lying time per 24 hours did not change at three or six months after surgery. Baseline accumulated steps per day averaged 6139 ± 2720 and did not change over time. Conclusions: Given that PA and sitting/lying time per 24 hours are believed to independently contribute to energy balance and health outcomes, clinicians and health professionals should intervene more rigorously to simultaneously reduce daily sitting time and increase levels of PA to help bariatric patients successfully manage their weight over the long-term post-surgery.