In this study, we analyzed the relationships between the segment energy and causal energy sources in soccer instep kicking. The dynamic model of kicking movement consists of 7 segments (trunk, right and left thighs, shanks and foots) and 18 degrees of freedom of joint motions including the trunk rotation, right and left hips, knees and ankles. The segment energy were decomposed into causal energy sources due to a joint torque, centripetal force, coriolis force, ground reaction force and so on. Results showed that the segment energies of the kicking thigh, shank and foot were primarily generated by the joint torque, centripetal force, coriolis force and ground reaction force-dependent powers. It is concluded that the joint torque- and motion-dependent interactions among the trunk, supporting leg and kicking leg play a role to transfer proximal segment energy to distal segment energy during instep kicking movement.