Purpose: Post-operative changes in moderate-to-vigorous physical activity (MVPA) may contribute to improved weight loss and long-term weight maintenance of individuals after bariatric surgery. Patients experience minimal changes in MVPA > 6 months after surgery, but no studies have investigated early changes in physical activity after surgery. This study aims to assess MVPA changes during the rapid weight loss phase through self-reporting and objective measures.
Methods: Physical activity patterns were assessed as minutes per day spent doing MVPA. A walking cadence of ≥ 100 steps per minute defined MVPA. Individuals completing gastric bypass (N = 7) and sleeve gastrectomy (N = 17) procedures (21 females, 3 males, age 42.2 ± 12.6 years, body mass 121.8 ± 24.8 kg, BMI 44.0 ± 6.5) completed office visits at 12 ± 6 days pre- and 35 ± 10 days post-operative. Each wore an ActiGraph GT3X tri-axial accelerometer at the hip for 7 days before and again for 7 days 30.6 ± 10 days after surgery. Assessments also included a subjective question about their anticipated and perceived post-operative MVPA (scale of - 3 to 3 with 3 being much more physically active and - 3 being much less).
Results: Participants did not change their minutes per day of MVPA significantly (pre-operative 1.5 ± 2.1; post-operative 2.6 ± 5.6, NS). Participants predicted their post-operative physical activity level would increase (2.8 ± 0.4). The self-reported activity level on the same scale after surgery was significantly less than predicted (1.9 ± 1.0, p < 0.05) but still suggested that participants thought they were more physically active.
Conclusion: Consistent with reports > 6 months after surgery, MVPA did not increase in the early post-operative period, despite patient expectations. The early post-operative period may be a time for behavioral intervention.
Keywords: Accelerometry; Obesity; Rapid weight loss; Sedentary behavior.