Obese subjects exhibit a reduced physical activity assessed by accelerometry

Aim: Reduced physical activity (PA) play a role in obesity. The amount and intensity of PA in free-living conditions is difficult to measure. The aim was to evaluate the usefulness of the accelerometer Actical (R) to measure PA and to discriminate potential differences between lean and obese subjects. Material and Methods: We studied information obtained with the Actical (R) and compared it with the SenseWear (R) ArmBand. PA of 46 lean (LE), 17 overweight (OW) and 31 obese (OB) volunteers. Anthropometric variables and blood biochemistry were analysed. Results: Data regarding PA obtained with the Actical (R) was similar independently of the location and comparable to the one obtained with the ArmBand. Obese subjects exhibited a reduced PA as evidenced by the amount of movement recorded by the accelerometer (LE: 357 +/- 16, OW: 338 +/- 23, OB: 298 +/- 14, counts/min P<0.05). The amount of PA showed a significant correlation with BMI (r=-0.38, P<0.05), waist circumference (r=-0.42, P<0.05), and circulating free fatty acids concentrations (r=-0.44, P<0.01). Conclusions: The accelerometer Actical (R) worn on the wrist represents a useful tool in the clinical setting allowing to discriminate differences between lean and obese subjects. A low PA level is accompanied by a worst lipid profile and higher insulin resistance, particullarly in obese subjects, increasing its cardiometabolic risk.