Simple Change in Initial Standing Position Enhances the Initiation of Gait

DALTON, E., M. BISHOP, M. D. TILLMAN, and C. J. HASS. Simple Change in Initial Standing Position Enhances the Initiation of Gait. Med. Sci. Sports Exerc., Vol. 43, No. 12, pp. 2352-2358, 2011. Purpose: Older adults and individuals with Parkinson's disease exhibit impaired gait initiation performance with less effective anticipatory postural adjustments (APA) and less dynamic stepping characteristics. These observations may reflect impaired interactions between the postural and locomotor components of this task. The purpose of this study was to evaluate the effectiveness of altering the stance position of the initial swing limb on improving APA characteristics and stepping performance. Methods: Three groups (healthy young adults, individuals with Parkinson's disease, and age-matched older adults) of 12 participants initiated gait from three initial stance conditions: normal, backward displaced swing limb, and forward displaced swing limb. Ground reaction forces and whole body kinematics were recorded to characterize the APA and step parameters. Results: Initiating gait from the back condition produced more forceful weight shifting (P < 0.001), greater propulsive forces (P < 0.001), and faster center-of-mass velocities throughout the stepping phases (P < 0.05). Conclusions: Translating the swing limb 0.5-ft-length backward seems to enhance the interaction between posture and locomotion, which may have therapeutic potential for improving gait initiation performance.