Biomechanical mechanism of Tai-Chi gait for preventing falls: A pilot study.

Tai-Chi (TC) practice has been increasingly used to prevent falls in older adults. However, the biomechanical mechanisms underlying the effects of TC practice on fall risk among older adults remain unanswered. The objective of this pilot study was to examine how TC gait biomechanically impacts the human body in terms of dynamic gait stability and lower limb muscle strength in comparison with regular walking gait. Ten healthy adults performed five trials of TC gait following three to seven trials of regular walking. Full body kinematics and kinetics were collected, and then dynamic gait stability and lower limb joint moments were determined. During TC gait, individuals were less stable, moved more slowly and experienced a larger mediolateral movement in comparison with regular walking gait. The peak moment at the ankle joint on the sagittal and transverse planes, at the knee joint on all three planes, and at the hip joint on the frontal plane was significantly different when performing TC gait than during regular gait. The results indicate that TC gait challenges body balance and requires more muscle strength of the lower limb joints compared to regular walking gait. To cope with these challenges, the body could develop neuromuscular control strategies to maintain body balance and thus reduce the risk of falls. The findings and methodology in this study could provide preliminary guidance for identifying optimal TC forms in order to maximize the effects of TC-based fall prevention interventions among various populations with elevated risk of falls.