2014, Volume 10
A biomechanical assessment of fajin mechanisms in martial arts
Jia-Hao Chang1, Yao-Ting Chang1, Chen-Fu Huang1
1Department of Physical Education, National Taiwan Normal University, Taipei, Taipei, Taiwan
Author for correspondence: Jia-Hao Chang; Department of Physical Education, National Taiwan Normal University, Taipei, Taipei, Taiwan; email: jhchang[at]ntnu.edu.tw
Background and Study Aim: As a martial arts technique, fajin (“exerting strength”) is a reasonable and efficient method of utilizing muscle strength. The purpose of this study was knowledge about fajin movement mechanisms in terms of muscle activation people practicing martial arts.
Material and Methods: A three-dimensional motion analysis system, force plates, and a wireless electromyography system were used to simultaneously collect kinematics, kinetics, and muscle activation from eight martial arts trainees who were familiar with fajin techniques. Statistical analysis was performed using Kendall’s coefficient of concordance at a significance level of α=0.05.
Results: The results revealed that the maximum joint angular velocities, maximum joint angles, initiation of muscle activations, and peak muscle activations occurred in a fixed sequence. The fajin motor pattern is initiated by a push from the rear foot, which produces a ground reaction force and moves the center of gravity forward. All of the joint operations and muscle activation timings occurred in a fixed sequence in this study.
Conclusion: Because traditional martial arts training uses descriptive language in the teaching process, muscle utilization differences can readily arise between individual martial artists. However, the body segments moved in a fixed order in all of the subjects, indicating that various martial arts approaches converge towards the achievement of the same objectives during a fajin. Future studies should specifically examine a number of top martial athletes and/or individuals who practice the same martial arts discipline. These examinations may elucidate the extent to which martial arts practices can be quantified and can contribute to identification of the optimal language and methodology for martial arts instruction.
Key words: action sequence, electromyography, ground reaction force, martial arts, muscle activation timing