Complex interplay between emotional states and gait parameters: a domain-specific investigation in healthy young adults.

Emotional states significantly influence human movement, yet specific relationships between naturally occurring moods and gait parameters remain poorly understood. This study investigated how naturally occurring mood states affect gait characteristics in young adults (n = 16), accounting for time-of-day variations and individual-level differences. Participants completed mood assessments and instrumented gait analysis across five sessions throughout an academic semester. Principal component analysis identified five distinct gait domains (phase, variability, rhythmicity, temporal, and spatial), explaining 84.67% of total variance. Linear mixed-effects models with random intercepts showed that negative moods distinctly affected temporal (β = 0.675, p = 0.012) and spatial (β = 0.522, p = 0.045) components, with anger and shame prolonging temporal measures and guilt and shame increasing spatial variability. Conversely, happiness shortened temporal measures (β=-0.568) and reduced spatial variability (β=-0.683), suggesting a stabilizing effect on gait dynamics. Substantial inter-individual variability emerged in phase organization (4.870), underscoring unique baseline differences in emotion-gait coupling. Morning sessions exhibited significantly faster gait speed (mean = 1.577 ± 0.296 m/s) and longer step lengths (mean = 80.070 ± 10.767 cm) compared to afternoon sessions (gait speed: mean = 1.311 ± 0.107 m/s; step length: mean = 71.903 ± 5.325 cm; p < 0.001). These findings confirm that distinct mood states elicit domain-specific gait changes and highlight the importance of circadian and individual factors for understanding embodied cognition and refining clinical gait assessments.