Fig. 1

Study organisation. The study was organized in 3 stages (A-C) separated by short gaps to enable data analysis, revision of activity circuits, device servicing/improvement and participant recruitment. Each stage consisted of a series of 1 h study sessions, each involving a different participant who undertook 4 activity circuits. One of the following interventions was applied during each circuit: no device (ND); device worn, no cueing (NC); device worn, responsive (FOG-initiated) rhythmic vibration cueing (RC); device worn, continuous rhythmic vibration cueing (CC). The ordering of these interventions was systematically alternated for each participant as indicated. Each circuit consisted of a series of activity segments: the number of activity segments completed per circuit was dependent on the ability of each participant, as indicated