Ambulatory gait monitoring over 24-h of activities of daily living. (A) Stride length data (blue squares) and periods of lying down (shaded boxes) determined by the gait monitor over 24-h of community living in a subject with PD. The activities were reported by the subject in a simple diary. The vertical arrows indicate when PD related medications were self-administered. (B) Detail of 10-min of stride length while shopping.