Assessment of Light-Intensity Activities and Sedentary Behaviors Using Multiple Measurement Devices

Purpose To examine the accuracy of three measurement devices (ActiGraph GT3x+, ActivPAL, and Sensewear Armband) in assessing sedentary behavior and light-intensity physical activity (PA) against a referent measure of oxygen uptake (Oxycon Mobile).

Methods 16 adults (8 males, 8 females) wore the four measurement devices while performing 7 activities (walking at 1.0 mph, 1.5 mph, 2.0 mph, cleaning a kitchen, standing and reading, typing at a computer, and playing board games) classified in the 2011 Compendium of Physical Activities between 1.2 and 1.8 METs or were unmeasured activities that were light-intensity in nature. Activities were classified as either sedentary or light-intensity according to the oxygen uptake, and the other measurement devices were compared against oxygen uptake for accuracy in measurement. Mean absolute percent error (MAPE) was used to calculate measurement accuracy.

Results The Sensewear Armband measured treadmill walking accurately (0% MAPE), but activities requiring arm movement were less accurate (typing – 50.00% MAPE). The ActivPAL also measured treadmill walking accurately (1.88% MAPE) but misclassified standing activities (reading – 86.88% MAPE). The ActiGraph GT3X+ misclassified activities with slow (<1.5 mph) walking (1.0 mph – 62.05% MAPE).

Conclusions The measurement device used to assess sedentary behavior may impact the amount of time spent in light-intensity PA or sedentary behaviors. Researchers should use caution when selecting a measurement device if the goal is to measure sedentary behaviors. Monitors designed to assess PA may not accurately assess sedentary behaviors. This research was supported by the Plus One Active Research Grant on Wellness from the American College of Sports Medicine Foundation.