Gait Adaptations Under Functional Asymmetry: Exploring the Role of Step Width, Step Length, and CoM in Lateral Stability

Bipedal gait is inherently unstable, requiring a complex interplay between foot placement and centre of mass (CoM) movement to maintain balance. While various factors are known to impact walking balance, few studies have explored the specific effects of functional asymmetry on lateral stability. This study investigates how step length, step width, and CoM adaptations impact lateral gait stability in healthy young adults walking with and without a functional asymmetry induced by fully extending the left knee. The results show that step length remains unaffected by functional asymmetry regardless of speed, while step width increases under the constraint. This adjustment increases the base of support; however, the concurrent increase in lateral CoM movement reduces overall lateral stability. These findings offer valuable insights into fundamental gait adaptation and stability mechanisms, with potential implications for designing rehabilitation strategies for individuals with gait asymmetry.