Journal of Sports Science and Medicine
Journal of Sports Science and Medicine
ISSN: 1303 - 2968   
Ios-APP Journal of Sports Science and Medicine
Androit-APP Journal of Sports Science and Medicine
from September 2014
©Journal of Sports Science and Medicine (2009) 08, 29 - 35

Combat Sports Special Issue 3, Research article
Comparison of Two Variants Of a Kata Technique (Unsu): The Neuromechanical Point of View
Valentina Camomilla1, , Paola Sbriccoli1, Alberto Di Mario2, Alessandro Arpante1, Francesco Felici1
Author Information
1 Department of Human Movement and Sport Sciences, University of Rome, Italy
2 FIJLKAM - National Judo, Karate, Wrestling and Martial Arts Federation, Roma, Italy

Valentina Camomilla
✉ Piazza Lauro de Bosis, 15 – 00135 Rome, Italy
Publish Date
Received: 01-03-2009
Accepted: 31-07-2009
Published (online): 01-11-2009
Share this article

The objective of this work was to characterize from a neuromechanical point of view a jump performed within the sequence of Kata Unsu in International top level karateka. A modified jumping technique was proposed to improve the already acquired technique. The neuromechanical evaluation, paralleled by a refereeing judgment, was then used to compare modified and classic technique to test if the modification could lead to a better performance capacity, e.g. a higher score during an official competition. To this purpose, four high ranked karateka were recruited and instructed to perform the two jumps. Surface electromyographic signals were recorded in a bipolar mode from the vastus lateralis, rectus femoris, biceps femoris, gluteus maximus, and gastrocnemious muscles of both lower limbs. Mechanical data were collected by means of a stereophotogrammetric system and force platforms. Performance was associated to parameters characterizing the initial conditions of the aerial phase and to the CoM maximal height. The most critical elements having a negative influence on the arbitral evaluation were associated to quantitative error indicators. 3D reconstruction of the movement and videos were used to obtain the referee scores. The Unsu jump was divided into five phases (preparation, take off, ascending flight, descending flight, and landing) and the critical elements were highlighted. When comparing the techniques, no difference was found in the pattern of sEMG activation of the throwing leg muscles, while the push leg showed an earlier activation of RF and GA muscles at the beginning of the modified technique. The only significant improvement associated with the modified technique was evidenced at the beginning of the aerial phase, while there was no significant improvement of the referee score. Nevertheless, the proposed neuromechanical analysis, finalized to correlate technique features with the core performance indicators, is new in the field and is a promising tool to perform further analyses.

Key words: Biomechanics, electromyography, technique analysis, karate

           Key Points
  • A quantitative phase analysis, highlighting the critical features of the technique, was provided for the jump executed during the Kata Unsu.
  • Kinematics and neuromuscular activity can be assessed during the Kata Unsu jump performed by top level karateka.
  • Neuromechanical parameters change during different Kata Unsu jump techniques.
  • Appropriate performance capacity indicators based on the neuromechanical evaluation can describe changes due to a modification of the technique.
Home Issues About Authors
Contact Current Editorial board Authors instructions
Email alerts In Press Mission For Reviewers
Archive Scope
Supplements Statistics
Most Read Articles
  Most Cited Articles
JSSM | Copyright 2001-2020 | All rights reserved. | LEGAL NOTICES | Publisher

It is forbidden the total or partial reproduction of this web site and the published materials, the treatment of its database, any kind of transition and for any means, either electronic, mechanic or other methods, without the previous written permission of the JSSM.

This work is licensed under a Creative Commons License Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.