Reduced gait speed and arm swing, shorter strides and increased gait variability are typical features of gait in Parkinson's disease (PD). From a temporal point of view, the absence of a steady gait rhythm and the subsequently more random stride-to-stride variability is a primary disorder and a clear indicator of elevated fall risk in PD. As an external form of cueing, Nordic walking (NW) may improve these gait deficits. This study aimed to evaluate the effects of NW on temporal organization of gait variability and spatiotemporal gait variables in PD.