2014, Volume 10, Issue 1
Biomechanics of the judo backward breakfall: comparison between experienced and novice judokas
Takanori Ishii1, Sentaro Koshida2, Tadamitsu Matsuda3, Toshihiko Hashimoto4
1Graduate school of Comprehensive Human Studies, University of Tsukuba, Tsukuba, Ibaraki, Center of Liberal arts Education, Ryotokuji University, Urayasu, Chiba, Japan
2Department of Judotherapy and Sports Medicine, Faculty of Health Sciences, Ryotokuji University, Chiba, Japan
3Department of Physical Therapy, Faculty of Health Science, Uekusa Gakuen University, Wakaba-ku, Chiba, Japan
4Center of Medical Education, Ryotokuji University, Urayasu, Chiba, Japan
Author for correspondence: Sentaro Koshida; Department of Judotherapy and Sports Medicine, Faculty of Health Sciences, Ryotokuji University, Chiba, Japan; email: koshida[at]ryotokuji-u.ac.jp
Background and Study Aim: Head injuries sustained during the sport of judo have gained significant public attention because of the incidence of severe cases among novice judokas in Japan. The judo backward breakfall skill may play an important role in decreasing the number of head injuries. Therefore, more effective ways to acquire appropriate judo backward breakfall skills are needed, and this requires a greater understanding of the breakfall movement. The aim of the study was to investigate the kinematics and muscle activation patterns during a judo backward breakfall in experienced and novice judokas.
Material and Methods: Eleven experienced judokas and 13 novice judo judokas volunteered for the study. Three-dimensional kinematic data were collected while participants performed five sets of backward breakfalls. We documented head-, neck-, trunk-, hip and knee-angle time profiles and electromyographic activities of the sternocleidmastoid, external oblique and rectus abdominis muscles during breakfalls.
Results: We found significant difference in the knee joint motion during the judo backward breakfall between the experienced and novice judokas. However, there were no significant differences in the activation patterns of any muscles between the experienced and novice judokas. In addition, the timing of hand impact appeared to coincide with the timing of peak head linear acceleration.
Conclusion: The knee joint movement and the hand impact skill may be important components of the judo backward breakfall motion.
Key words: electromyography, head injuries, kinematics, martial arts