Eric Siau

Line

THE SYMMETRY IN KINEMATICS BETWEEN

THE DOMINANT AND NON-DOMINANT LEGS IN TAEKWONDO

TURNING KICK

SIAU JUN XIONG

A report submitted in partial fulfillment of the requirement for award of the degree of

Bachelor of Science and Education (Sport Science)

Faculty of Education

Universiti Teknologi Malaysia

APRIL 2009

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DEDICATION

To my beloved mother, father and my family.

For their love, patience and support.

They would be very proud of me.

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ACKNOWLEDGEMENT

I would like to thank a lot of people who have contributed towards finishing

this thesis.

First and foremost, I am very grateful to my dearest Supervisor, Hjh Hafizah

Harun for her guidance and patience given to me throughout my entire thesis

preparation. Pn. Hafizah has been a wise lecturer and an excellent mentor to me. This

thesis would not have been completed without her.

Secondly, I would like to thank my Taekwondo friends; Mr. Lee Poh Hau

who let me used his studio for free, Mr. Jaysuman and my subjects. I would like to

express my sincere gratitude to Ms. Woo Mei Teng, my senior who shared her

knowledge in using the SiliconCoach software. To all my course mates who have

been a great support and helping me in these 4 years. We are just like family.

Last but not least, I want to acknowledge the contribution of many people

who, directly or indirectly assisted me through out the preparation of my thesis.

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ABSTRACT

The objective of this study was to determine the differences between

dominant and non-dominant leg in Taekwondo Turning Kick. There were 5 subjects

who are Johor state national level black belt Taekwondo players with the mean age

21.71 ± 2.58 years old, mean weight 55.87 ± 6.76 kg and mean height 170.22 ± 5.41

cm. This research was carried out in the XF Dance and Martial Arts Studio, located

in Bandar Putra, Kulai, Johor. A Sony DCR-HC38 digital video camera with 25

frames per second (fps) was used for the sagittal view recording. Movements

analysis software - SiliconCoach 7 were used in the digitizing process, which were

done manually with a reference point marked at the tarsal bone. The results were

focused, firstly, on the comparison of the dominant and non-dominant kicking speeds

and secondly, the relationship between the vertical kicking angle and the maximum

height at the target spot. The results showed that mean peak velocity for the

dominant and non-dominant kick were 12.93 m/s and 12.27 m/s respectively. T-test

showed that there were no significant differences in velocity between dominant and

non-dominant legs in Taekwondo turning kick. Therefore the null hypothesis of this

research was achieved. The mean dominant vertical angle was lower than the mean

non-dominant angle which were 70.62° and 72.68° respectively, whereas the mean

height of the kick by dominant leg was higher than mean height of the kick by non-

dominant leg (1.23m and 1.20m respectively). In conclusion, the expert Taekwondo

players were equally fast and efficient during the turning kick when using both

dominant and non-dominant legs.

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ABSTRAK

Kajian ini adalah bertujuan menyelidik perbezaan di antara kaki dominant

dengan kaki bukan dominant dalam Taekwando Turning Kick. Subjek terdiri

daripada 5 orang atlit negeri Johor yang berperingkat kebangasaan dengan min umur

21.71 ± 2.58 tahun, min berat badan 55.87 ± 6.76 kg serta min ketinggian 170.22 ±

5.41 cm. Kajian ini dijalankan di XF Dance and Martial Arts Studio yang terletak di

Bandar Putra, Kulai,Johor. Kamera video digital Sony DCR-HC38 yang mempunyai

25 frames per second (fps) digunakan untuk rakaman sagittal. Perisian analisis

pergerakan- SiliconCoach 7 digunakan dalam proses digitasi. Proses digitasi

dilakukan secara manual dengan melibatkan satu titik rujukan pada atas tulang tarsal

kaki. Dapatan kajian ini menumpu pada 2 bahagian. Pertama, perbandingan kelajuan

tendangan antara kaki dominant dengan kaki tidak dominant. Kedua, hubungan

antara sudut tendangan menjajar dengan ketinggian maxima pada sasaran. Dapatan

kajian ini menunjukkan min halaju maxima bagi kaki dominant dan kaki bukan

dominant adalah 12.93 m/s dan 12.27 m/s masing-masing. Dapatan T-test

menunjukkan tidak terdapat perbezaan yang signifikan di antara halaju kaki

dominant dengan halaju kaki bukan dominant dalam Taekwando turning kick

walaupun halaju kaki dominant lebih tinggi daripada halaju kaki tidak dominant.

Hipotesis nol untuk kajian ini dicapai. Min sudut menjajar untuk kaki dominant

adalah lebih rendah daripada min sudut menjajar kaki bukan dominant iaitu 70.62°

dan 72.68° masing-masing. Walaubagaimana pun, min ketinggian maxima tendangan

kaki dominant adalah lebih tinggi daripada min ketinggian maxima kaki bukan

dominant iaitu 1.23 m dan 1.20 m masing-masing. Kesimpulan, pakar pemain

Taekwando mempunyai kelajuan dan keberkesanan semasa turning kick semasa

menggunakan kaki dominant dan kaki bukan dominant.

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TABLE OF CONTENTS

CHAPTER TITLE PAGE

1

TITLE PAGE

DECLARATION OF ORIGINALITY

DEDICATION

ACKNOWLEDGEMENT

ABSTRACT

ABSTRAK

TABLE OF CONTENTS

LIST OF TABLES

LIST OF FIGURES

LIST OF APPENDICES

INTRODUCTION

1.1 Overview

1.2 Background of Problem

1.3 Statement of Problem

1.4 Objectives

1.5 Scope

1.6 Significance of Study

1.7 Hypothesis

1.8 Limitations

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1.9 Conclusion

LITERATURE REVIEW

2.1 Introduction

2.2 Taekwondo Kicks

2.3 Dominant and Non-dominant Limbs

2.4 The Turning Kick

2.4.1 Anatomy of the Turning Kick

2.4.2 Mechanical of the Turning Kick

2.5 Conclusion

RESEARCH METHODOLOGY

3.1 Introduction

3.2 Research Design

3.3 Subject Selection

3.4 Venue

3.5 Instrument

3.6 Measurement Equipment

3.7 Research Procedures

3.7.1 Subject Selection Procedures

3.7.2 Research Protocol

3.7.3 Data Collection Procedures

3.7.4 Data Analyse Procedures

3.8 Conclusion

DATA ANALYSIS

4.1 Introduction

4.2 Average for All the Subjects

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4.2.1 Comparison of All Subjects’ Dominant and

Non-dominant Kicking Velocity

4.2.2 The Relationships Between the Vertical

Kicking Angle and the Maximum Height

of Kicks at the Target Area

4.3 Subject A

4.3.1 Comparison of Subject A’s Dominant and Non-

dominant Kicking Velocity

4.4 Subject B

4.4.1 Comparison of Subject B’s Dominant and Non-

dominant Kicking Velocity

4.5 Subject C

4.5.1 Comparison of Subject C’s Dominant and Non-

dominant Kicking Velocity

4.6 Subject D

4.6.1 Comparison of Subject D’s Dominant and Non-

dominant Kicking Velocity

4.7 Subject E

4.7.1 Comparison of Subject E’s Dominant and Non-

dominant Kicking Velocity

DISCUSSION, CONCLUSION AND

RECOMMENDATIONS

5.1 Introduction

5.2 Discussion

5.2.1 Dominant Vs Non-Dominant leg

5.2.2 Quantitative Analysis

5.2.3 Qualitative Analysis

5.2.4 Suggestion to Improve the Symmetry of

Dominant and Non-dominant Leg Kicking

Speed

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5.2.5 The Relationship Between The Vertical Angle

and The Height of The Kick on The Target

Spot

5.3 Conclusion

5.4 Recommendation

5.4.1 Subject Selection

5.4.2 Video Recording

5.4.3 Location Setup

5.4.4 Digitizing

5.5 Summary

BIBLIOGRAPHY

APPENDIX

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LIST OF TABLES

TABLE NO. TITLE PAGE

2.1

4.1

4.2

4.3

4.4

4.5

4.6

4.7

4.8

The t-test of kinematics characteristics of preferred leg

and non-preferred leg during turning kick (mean ± SD)

Details of all the subjects

Average D and ND leg kicking velocity for all subjects

(n=5)

The average of the vertical kicking angle and the

maximum height of kicks at the target area

A’s D and ND leg kicking velocity

B’s D and ND leg kicking velocity

C’s D and ND leg kicking velocity

D’s D and ND leg kicking velocity

E’s D and ND leg kicking velocity

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LIST OF FIGURES

FIGURE NO. TITLE PAGE

2.1

2.2

4.1

4.2

4.3

4.4

4.5

4.6

4.7

4.8

The mean joint velocity patterns of preferred leg during

turning kick from the moment of toe lift off to target

contact. (n=6)

The mean joint velocity patterns of non- preferred leg

during turning kick from the moment of toe lift off to

target contact. (n=6)

Average D and ND leg kicking velocity from all subjects

(n=5)

The average of the vertical kicking angle

The average maximum height of kicks at the target spot

A’s D and ND leg kicking velocity

B’s D and ND leg kicking velocity

C’s D and ND Leg Kicking Velocity

D’s D and ND leg kicking velocity

E’s D and ND leg kicking velocity

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LIST OF APPENDICES

APPENDIX TITLE PAGE

A

B

C

D

E

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Personal Details Form for Subject

T- test For the Dominant and Non-Dominant Kicking

Velocity

Digitizing Interface From The Software SiliconCoach

Result Showed in Software SiliconCoach (Speed)

Result Showed in Software SiliconCoach (Angle)

Result Showed in Software SiliconCoach (Height)

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CHAPTER 1

INTRODUCTION

1.1 Overview

Taekwondo is not merely a form of Korean martial arts for self-defence

against assailants and wild animals. It is also a form of physical exercise to develop

ones strength and agility as well as to maintain both physical and mental health.

Taekwondo is distinct from Chinese Kung Fu and Japanese Karate. “Tae”

(Hangul: 태, hanja: 跆) means to kick, attack or defend with the feet. “Kwon”

(Hangul: 권, hanja: 拳) means to punch, strike, or smash with the hand or fist to

defend and attack. “Do” (Hangul: 도, hanja: 道) means the art and the way, the

methodology of application of our human body parts.

Taekwondo is known as one of the combat-oriented sport. This sport uses

only hands and feet without any weapons. Due to the unique variety of kicking

techniques practiced in Taekwondo, many people have come to call it the “Kicking

Martial Arts” although it also practices a fair amount of hand and fist techniques.

Taekwondo is famed for its use of kicking techniques, which distinguishes it

from others martial arts. Under the latest World Taekwondo Federation (WTF) rules

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and regulations, sparring takes place between two competitors in an area measuring

10 meters square. Each match or bout consists of three non-stop rounds of contact.

Breaks are given between rounds. Points are awarded for permitted, accurate and

powerful techniques to the legal scoring areas. Light contact or insufficient impact of

kicking to the scoring area does not merit any points. Unlike soccer which

determines its’ winners easily by the total number of goals, Taekwondo is “a very

subjective sport” when it comes to scoring. “Even if you have one of the best fights of

your life, you can still lose based on the scoring.”(Cogan, 2008).

Among the main kicking technique in Taekwondo, turning kick is the most

preferred technique. Lee (1998) showed 50% of the kicks made by males are turning

kick. Of all the kicks used to score, 89% are turning kicks. Moreover, 79% of the

kicks made by females are turning kicks. These data shows that both male and

female use turning kick as the main kicking technique to score the point ( Kim &

Kim, 1997).

In Taekwondo, one has to move all the muscles and joints of the human body.

Therefore, it involves the dominant and non-dominant limbs in the kicking

techniques. Taekwondo athletes may be filled with anxiety having to anticipate the

opponents’ techniques, and over scoring instead of worrying about the training

conditions. Therefore, the turning kick relationship between the dominant and non-

dominant leg plays an important part in the training program.

The main aspect of the turning kick is the speed of lifting the knee. According

to the biomechanical definition, the purpose for this movement is to decrease the

Moment of Inertia (MoI) of the segment and decrease the distance between segment

from the axis of rotation to a point (the radius of rotation, r). All of these refer to the

segment against the rotation while doing the kick and the rotation is predominant by

the waist. Therefore, the lack of the MoI will produce a faster rotation against the

joint. This basic movement provides an advantage because it increases the potential

to produce a variety of kicks using the same mechanical movement.

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1.2 Background of Problem

The main biomechanical principle in Taekwondo is the sequential motions,

which refers to the coordination of the body segment to achieve a high speed motion

at the end of movement. Fast unloaded movement (attacking, throwing and kicking)

are performed typically in a proximal to distal fashion (the nearest segment to the

body - thigh, to the segment that furthest away from the body – leg.) The purpose of

this movement is to achieve a high speed at the end of the sequential movement in

order to produce a powerful strike.

Most instructors and coaches emphasize on the turning kick technique. They

want to know the best method for the turning kick so their athletes could perform the

fastest and most powerful kick. The combination factors such as psychology,

physiology and the biomechanics movement contributes to the speed and power of

the turning kick.

The turning kick, which was designed by General Choi, is designed to be

used while wearing combat boots, so the toes does not have to be curled backwards

but in competitions, kicking is done barefooted. There were a lot of complaints on

the “slower speed” of the turning kick and toe injuries resulted from kicking training

bags with the ball of the foot, so a different type of turning kick was developed.

The use of instep kicking and a knee whip motion with an impact that pushes

beyond the target is introduced. Taekwondo sport athletes’ uses the instep kicking

technique because it has better range while sparring. Besides that, Taekwondo

athletes need to constantly anticipate the movement of their opponent in order to

counter with the most effective counter-attack techniques. Hence, both mental and

physical speeds are the key factors to win in the competition-oriented Taekwondo

style for the Olympics.

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The height of the kick which a Taekwondo athlete is able to reach is an

important issue in the sparring training as any attack below the waist is not permitted

in the rule and regulations of WTF.

Everyone has dominant and non-dominant limbs. For example, right-handed

people would prefer to use their right limbs more frequently than the left, and vice

versa. Therefore, a lot of athletes especially the beginners prefer to train their

dominant limb as compared to the non-dominant. This is because they feel more

comfortable using their dominant hand and leg which also boost their confidence

level in their kick.

1.3 Statement of Problem

Instructors should know of the difference between the kicking

movement of the dominant and non-dominant limbs so they can assist their

athletes on ways of improving their performance. Furthermore, they can also

create tailor-make training programs according to each athlete’s abilities

based on this research. This research should benefit all Taekwondo

instructors and players alike.

1.4 Objectives

The objectives of the present study are to analyse:

1.4.1 The differences in speed between the dominant and non-dominant leg during

the turning kick.

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1.4.2 The differences of the kicking angle between the dominant and non-dominant

leg during the turning kick.

1.4.3 The differences height at the target spot between dominant and non-dominant

leg while using turning kick.

1.5 Scope

This research focuses on 5 male national level Taekwondo athletes. These

subjects have been black-belt holders for at least 2 years and have won several

medals in the national level tournament in 2008.

1.6 Significance of Study

Turning kick has been known as the most popular kicking technique in the

tournament. According to Lee (1998), it is also the most common technique used to

score points compared to other kicking techniques available in Taekwondo

competition. Turning kick is by far the fastest kicking technique compared with other

kicks.

This research also aims to identify the kinematics parameter between the

dominant and non-dominant leg during turning kick. This study will help the subject

and coaches to know the ability about oneself. The coach can help the subjects to

improve their performance in the turning kick based on this research.