The Effect of Arm Swing and Asymmetric Walking on Gait Kinetics in Young Adults

Abstract

Introduction: Asymmetric gait is prevalent among older adults as well as in people with gait pathologies (e.g., Parkinson’s disease, following a stroke) and has been linked to a higher risk of falls. While a certain level of gait asymmetry is present in healthy young adults, the simulation of larger asymmetry in this population provides information about efficient strategies to regulate dynamic stability. Research investigating gait asymmetry has described spatiotemporal and kinematic strategies. However, limited information is available regarding changes in gait kinetics. Research objectives: This thesis aims to determine the gait control strategies utilized by young adults to regulate simulated gait asymmetry combined with different arm movement amplitude. We hypothesized that the hip joint would be the most affected by different arm swing conditions and asymmetric gait. We also hypothesized that asymmetric gait and active arm swing would lead to increased variability in the lower-limb movements. Methods: Fifteen healthy young adults (23.4±2.8 years, 7 Females) walked with three arm swing conditions (held, normal, and active) during symmetric and asymmetric walking conditions. The CAREN-extended System (Motek Medical, Amsterdam, NL) was used for data collection. Outcome measures included step length and width mean and variability (meanSD), vertical ground reaction forces, and lower-limb joint moment impulse mean and variability (meanSD) in the sagittal and frontal planes. Results: When comparing arm swing conditions, the active arm swing led to an increase in step width variability, vertical ground reaction forces, hip and knee variability in the sagittal plane, ankle abduction moment for the fast leg, as well as in knee variability in the frontal plane. As for gait symmetry, the asymmetric condition led to increased step width for the fast and slow legs and increased vertical ground reaction forces for the slow leg. The asymmetric condition further prompted adjustments in the frontal and sagittal planes, particularly at the ankle and hip joints during the braking phase, and in the knee joint during the propulsion phase phases when compared to the symmetric walking condition. Conclusion: Findings suggest that participants increased hip activity to control the effect of arm motion on the trunk to minimize adaptations in the lower-limb joints. The asymmetry condition demonstrated that participants searched for flexible lower-limb strategies aimed at minimizing bilateral differences between the fast and slow legs during asymmetric walking.