Gait Response to Rhythmic Cues: Influence of Adaptation Mechanisms and Entrainment Levels.

This study categorizes the response to asymmetric rhythmic cues into distinct levels of adaptation using changes in their step velocity. Motion capture and force data were collected from healthy individuals undergoing split-belt treadmill and rhythmic cueing interventions. This allowed comparative insights into two distinct adaptation mechanisms (sensorimotor and instructional adaptation) corresponding to the interventions and integration of those findings with trade-off mechanisms within spatiotemporal and kinetic gait parameters. Interlimb gait harmony (corresponding to differences between left and right step velocities) was significantly different between the gait interventions, indicating underlying differences in the dominant adaptation mechanisms driving them. The trade-off mechanisms among step length, swing time, and push-off forces were significantly different (i) between the gait interventions and (ii) between adaptable and non-adaptable subject groups to external rhythmic cues. This suggests that an orthogonal linear relationship between propulsion and either spatial or temporal features may indicate the adaptation mechanism that has a greater contribution towards their motor outcome.