Enhancing Locomotor Performance by Modulating Shoe Cushioning Properties

Abstract

The goal of this work was to determine if and how footwear properties could be modified to alter walking biomechanics. A test shoe was developed to allow heel and forefoot midsole cushioning to be quickly and independently varied. A systematic gait analysis study of 8 healthy human participants was performed to isolate and quantify the effects of shoe cushioning. Walking data were collected using a force-instrumented treadmill and infrared motion-capture system. Center-of-mass (COM) power, joint (ankle, knee, and hip) power, and deformable foot power were computed from these kinematic and kinetic data. Peak power and work summary measures were computed for key phases of the gait cycle: for push-off (the end of stance phase) and collision (immediately after foot contact). As hypothesized, forefoot cushioning primarily affected push-off power, with little effect on collision. Similarly, heel cushioning affected collision power, with minimal effect on push-off. COM peak push-off power was found to increase with softer forefoot cushioning and COM peak collision power became more negative with softer heel cushioning. Lower forefoot bending stiffness was also observed to increase peak COM push-off power. Therefore, a shoe intended to increase push-off power (e.g., for gait rehabilitation) might be designed with a soft and flexible forefoot midsole. These findings inform how shoe cushioning could be modulated to augment locomotor performance.