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Jpn J Biomechanics Sports Exercise 7(4):272-278, 2003

Effects of foot orthotics on reduction of ground reaction forces during running

Ryuji KAWAMOTO1), Yusuke ISHIGE2), Takashi MOCHIDA2), Takeshi YOSHIHISA2), Senshi FUKASHIRO3)

1)Faculty of Policy Management, Keio University
2)Yokohama Sports Medical Center
3)Department of Life Sciences(Sports Science), The University of Tokyo


The purpose of this study was to confirm quantitatively the effect of foot orthotics on the reduction of ground reaction forces during running. Twenty‐seven volunteers participated in this study. Ground reaction force(GRF)data were obtained from the subjects while running in two insole conditions (control and orthotic ones). The foot orthotics used in this study had mechanical functions to support medial longitudinal arch and rearfoot. Peak sideward GRF around heel-contact significantly reduced at 32% for the orthotic condition compared to the control one (P<0.05). Cluster analysis based on the time series of sideward GRF data enabled to categorize the subjects into four representative groups. Peak sideward force significantly reduced at 54% for the orthotic condition (P<0.01) for the group in which the subjects showed high heel-contact impact (more than 2.5N/g). These results suggested that well-designed foot orthotics could effectively reduce sideward impact force around heel-contact during running.

Key Words: foot orthotics, running, ground reaction force, cluster analysis

Submittted for Publication : June 3, 2003,

Accepted for Publication : September 5, 2003



JJBSE バイオメカニクス研究