The effect of running shoe midsole hardness on foot biomechanics

Abstract

The purpose of this study was to investigate whether placing harder midsole materials on the medial and posterior side of the outsole in a running shoe can change biomechanics variables during the stance phase of running. Ten healthy young recreational male runners (age: 20.5±0.7 yrs, mass: 73.1±3.8 kg, height: 176.8±2.9 cm) participated in this study. A shoe company (FILA, Korea) produced the same shoe with four different types of midsole density. Each subject wore the four different running shoes in randomized order while running on an instrumented treadmill at two speeds (3.5 m/sec and 4.5 m/sec). The positions of the markers and the ground reaction forces were recorded using a system of eight high speed motion capture cameras and force plates at a sampling frequency of 100 Hz and 1000 Hz, respectively. The variables of this study were the running parameters, ground reaction forces, and joint angles. This study was intended to investigate whether medially posted midsole materials in a running shoe effectively reduce foot pronation and other running biomechanics variables. However, there was no modified shoe effect on most running kinematics and kinetics except the impact loading rate. It is concluded that other features of shoe manufacturing in terms of structures and materials should be considered to understand the function of anti-pronation in a running shoe.