Physical Activity After Surgically Obtained Weight Loss: Study with a SenseWear Armband in Subjects Undergoing Biliopancreatic Diversion

This study aimed to understand the role of the extra load of body mass in limiting physical activity and in preventing an active lifestyle in severely obese patients. The study was carried out in a University Hospital setting, and investigates severely obese patients, having undergone biliopancreatic diversion (BPD) for obesity and control subjects with a body weight closely similar to that of the BPD subjects; energy intake was evaluated by alimentary interview and energy expenditure was assessed with the Body Media SenseWearA (R) Pro armband (SWA). SWA metabolic efficiency (MET) was negatively associated with body mass index values (rho = -0.464, p < 0.01), and the SWA overall energy expenditure was very similar to the energy alimentary intake in the obese patients and in the control subjects. Among the controls, the MET mean value was higher (p < 0.05) than that observed both in obese and in BPD subjects (1.392 +/- 0.211 vs. 1.149 +/- 0.181 and 1.252 +/- 0.284, respectively); furthermore, in comparison with the obese and the BPD groups, among the control individuals a greater number of active persons (27 % vs. 0 and 7 %, respectively) and a lower number of sedentary persons (27 % vs. 70 and 43 %, respectively) was found (p < 0.01). These preliminary results suggest the reliability of SWA data in assessing energy expenditure and tend to rule out the hypothesis that in severely obese patients the extra load of body mass by itself is a main factor limiting physical activity and leading to a sedentary lifestyle.