Lower Limb Biomechanics during Stair Descent are Related to the Descent Velocity of Healthy Young Individuals

Abstract

[Purpose] The purpose of this study was to examine whether lower limb biomechanics during stair descent is related to the descent velocity of healthy young individuals. [Subjects] Twenty young healthy subjects (12 males, 8 females, range 20-28 years) participated in this study. [Methods] The subjects descended the stairs in three cadences, paced by a metronome. Lower extremity biomechanical data was obtained using a 3D motion analysis system and two force plates. [Results] As stair descent velocity increased, the knee extensor moment and the ankle plantar-flexor moment at the early stance phase became larger, and the knee flexion and ankle dorsiflexion angles increased. On the other hand, the second peak of the knee extensor moment in the late stance phase was lower, and the knee flexion angle became smaller. [Conclusion] This study revealed that the lower limb biomechanics during stair descent is related to the velocity of stair descent.