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Relation between soccer shoe stiffness and kicking ball velocity

Performance in soccer depends primarily on the athlete, but is also influenced by the footwear as an important link to playing surface and ball (Rodano et al. 1988). Therefore, the development of soccer shoe properties underlies a continuous improvement that is partially based on biomechanical and mechanical tests. Kicking is a fundamental skill in the soccer game. To date, research has focused on raising ball velocity by changing the stiffness of shoe outsole materials. Sterzing and Hennig (2008) showed that modifications in outsole stiffness have no significant effect on ball velocity. However, the relation between stiffness of the complete soccer shoe and ball velocity is still unclear.