2014, Volume 10, Issue 1
Factors influencing the effectiveness of axe kick in taekwon-do
Jacek Wąsik1, Gongbing Shan2
1Institute of Physical Education and Tourism, Jan Długosz University of Czestochowa, Poland
2Department of Kinesiology, University of Lethbridge, Canada, College of Sport, Shaanxi Normal University, China
Author for correspondence: Gongbing Shan; Department of Kinesiology, University of Lethbridge, Canada, College of Sport, Shaanxi Normal University, China; email: g.shan[at]uleth.ca
Background and Study Aim: Taekwon-do is famous for its powerful kicking techniques and the axe kick is the challenging one, aiming at kicking high section of an opponent. The relevance of the skill in the traditional version of taekwon-do is that a single strike might happen to reveal the winner. The main aims of the study were 1) the kinematic characteristics of the axe kick using motion capture technology and 2) the kinematics conditions leading to maximization of kick effectiveness.
Material and Methods: Six International Taekwon-do Federation (ITF) practitioners participated in the study and each of them performed the axe kick (neryo chagi) three times. Using a 3D motion capture technology, selected parameters such as maximum kick foot velocity, durations of take-off, the upswing, the downswing as well as the whole kick and the kick leg angle at maximum velocity were quantitatively determined. The basic descriptive statistics (means & standard deviations) and correlation analyses were performed for revealing the dominant factors related to the kick.
Results: The results indicate that the maximum kick power appears around 45º of the kick leg to vertical direction or 85-89% of one’s body height (i.e. the optimal offence/attack height) during the downswing. The variation of the optimal offense height depends on one’s body height, gender and race. And the keys for increasing the kick effectiveness are balanced weight transfer, large hip ROM for pre-lengthening hip extensors and follows an explosive foot downswing for maximizing kick-foot power.
Conclusions: The following conclusions have been made on the ba¬sis of the above observations: the maximal kick power occurs around 45° of the kick-leg to the vertical direction during the downswing; shortening the downswing phase could increase the axe kick quality further.
Key words: 3d motion capture, biomechanical analysis, maximal kick velocity, optimal offence height, taekwon-do