Although several studies have examined the soccer kick (3,10 –13,17), most were done on the quasi-planar aspects of the instep kick or similar maximal soccer kicks. Thus,
minimal information is available especially for the side-foot kick. Recently, Levanon and Dapena (9) compared the three-dimensional angular motions required in the side-foot
kick with those required in the instep kick. However, no study has focused on the three-dimensional kinetics of these kicking techniques. Thus, the true kinetics of the two kicks have not been quantified appropriately. For understanding how the leg swing is produced in both kicks, it is necessary to identify its three-dimensional kinetic aspects. The purpose of this study, therefore, was to investigate the kinetic aspects of the two soccer kicks, side-foot and instep kicks, using a three-dimensional video analysis technique.