“Stepping Up” Activity Poststroke: Ankle-Positioned Accelerometer Can Accurately Record Steps During Slow Walking

Background As physical activity in individuals post-stroke is low, devices that monitor and provide feedback of walking activity provide motivation to engage in exercise and may assist rehabilitation professionals in auditing walking activity. However, most feedback devices are not accurate at slow walking speeds. Objective This study assessed the accuracy of one accelerometer, the Fitbit One, to measure walking steps of community-dwelling individuals post-stroke. Design Cross-sectional study Methods Two accelerometers were positioned on the non-paretic waist and ankle of participants (n=43) and walking steps from these devices were recorded from seven speeds (0.3-0.9m/s) and compared to video recordings (gold standard). Results When positioned at the waist, the accelerometer had more than 10% error at all speeds, except 0.8 and 0.9m/s, and numerous participants recorded zero steps at 0.3-0.5m/s. The device had 10% or less error when positioned at the ankle for all speeds between 0.4-0.9m/s. Limitations Some participants were unable to complete the faster walking speeds secondary to their walking impairments and inability to maintain the requested walking speed. Conclusions Although not recommended by the manufacturer, positioning the accelerometer at the ankle (compared to the waist) may fill a long-standing need for a readily available device that provides accurate feedback for the altered and slow walking patterns that occur with stroke.