In a small case-control study of medicated Parkinson patients, a fractal metronome improved stride-time fluctuation structure while listening to music increased gait velocity, stride length, and arm swing compared with no cue or a regular metronome.

This paper supports nonpharmacologic auditory cueing (music or fractal metronome) as clinically useful rehabilitation strategies and highlights stride-time DFA as a sensitive outcome measure for gait interventions, but it offers limited direct insights for molecular or drug-target discovery.

IMPORTANCE: Persons with Parkinson walk slowly, with short steps, reduced arm swing, and altered stride variability. Walking to a metronome or music may increase velocity, stride length, and cadence, yet few studies have directly compared the efficacy of these techniques. OBJECTIVE: To determine the optimal auditory cue to improve Parkinson gait. DESIGN, SETTING, AND PARTICIPANTS: This case-control study was conducted among persons with Parkinson disease (using medication) and healthy older adult controls at University of Florida Applied Neuromechanics laboratory in 2017. Changes in gait in participants with Parkinson disease and controls were compared with walking with no cue: walking to a regular metronome, walking to a fractal metronome, and walking to music. Condition order was randomized. Cueing frequency was set to natural cadence. Post hoc analyses restricted to participants with Parkinson disease were performed in 2026. EXPOSURES: Auditory cueing with a regular metronome, fractal metronome, or music while walking. MAIN OUTCOMES AND MEASURES: Outcomes of interest were stride time detrended fluctuation analysis (DFA), velocity, stride length, and arm swing velocity. Spatiotemporal gait measures and DFA of stride time were compared using repeated measures multivariate analysis of variance. RESULTS: Analyses included 15 participants with Parkinson disease (mean [SD] age, 69 [6] years; 11 [73%] male; mean [SD] Hoehn and Yahr Parkinson disease stage. 2.3 [0.6]; mean [SD] age of onset, 63 [7] years) and 15 controls (mean [SD] age, 69 [5] years; 11 [73%] male). Stride time DFA was increased during the fractal metronome condition (α = 0.200; SE, 0.024; P < .001) vs no cue, the regular metronome (α = 0.320; SE, 0.032; P < .001), and music (α = 0.219; SE, 0.030; P < .001); worsened with the regular metronome vs no cue (α = -0.120; SE, 0.037; P = .003); and was not statistically different during music vs no cue (α = -0.019; SE, 0.031; P = .54). Music was associated with increased velocity (mean [SE] change, 0.041 [0.015] m/s; P = .01), stride length (mean [SE] change, 0.047 [0.013] m; P = .001), and arm swing velocity (mean [SE] change, 27.10 [7.33] °/s; P = .001) compared with no cue; velocity (mean [SE] change, 0.030 [0.011] m/s; P = .03), stride length (mean [SE] change, 0.034 [0.009] m; P = .002), and arm swing velocity (mean [SE] change, 34.7 [8.5] °g/s; P = .001) compared with the regular metronome; and increased stride length (mean [SE] change, 0.028 [0.009] m; P = .01) and arm swing velocity (mean [SE] change, 37.52 [7.89] °/s; P < .001) compared with the fractal metronome. Analyses restricted to participants with Parkinson disease found similar trends, with reduced levels of significance due to the smaller sample. CONCLUSIONS AND RELEVANCE: In this case-control study, walking to the fractal metronome was associated with improved stride time fluctuations compared with the regular metronome or music. Walking to music was associated with improved velocity, stride length, and arm swing velocity compared with either metronome condition.