Biomechanical Responses of Instep Kick between Different Positions in Professional Soccer Players

The purpose of this study was to investigate some selected biomechanical characteristics of lower extremity between professional soccer defenders, midfielders and strikers. The kicking motions of dominant legs were captured from fifteen Olympic professional soccer players; (height: 181.93 ± 7.03 cm; mass: 70.73 ± 10.85 kg; age: 20.8 ± 0.77 years), volunteered to participate in this study, using four digital video cameras. There were significant differences between midfielders and defenders in (1) lower leg angular velocity (p ≤ 0.001), (2) thigh angular velocity (p ≤ 0.001), (3) lower leg net moment (p ≤ 0.001), (4) thigh net moment (p ≤ 0.001), and (5) ball velocity (p ≤ 0.012). There were significant differences between midfielders and strikers in lower leg net moment (p ≤ 0.001). There were si gnificant differences between strikers and defenders in; (1) lower leg angular velocity (p ≤ 0.001), (2) thigh angular velocity (p ≤ 0.001), (3) lower leg net moment (p ≤ 0.001), (4) thigh net moment (p ≤ 0.001), and (5) ball velocity (p ≤ 0.024). In conclusion, midfielders can perform soccer instep kicking strongly and faster than defenders and there is, however, no significant difference between midfielders and strikers, but midfielders` ball velocity is higher than strikers` ball velocity.