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1
Statement of originality
2
Acknowledgements
I would like to thank all of the participants for giving up their free time and
taking part in this study. I would like to thank my brother, Richard Jahn for
inspiring me to begin martial arts and giving me the tools I needed to
progress in my career. I would like to thank my Muay Thai coach, Wech
Pinyo for all of the hours of hard work he has spent with me and having
the faith in me to become a professional fighter.
3
Abstract
Introduction
Muay Thai is a combative sport in which competitors punch, kick, knee, elbow and grapple their opponents. The roundhouse kick is considered a fundamental weapon in Muay Thai which targets the side of the head, jaw, shoulders, rib cage, abdomen or legs of the opponent. The aim of the study was to determine the kinematic factors most closely related to a high velocity roundhouse kick. It was hypothesised that the speed of the heel during the final phase would be the most influential factor in producing a high velocity kick. The subjects used for this study were 6 Muay Thai practitioners recruited from ‘Hybrid MMA’ gym, Plymouth. Subjects mean age was 24.1 (4.2) yrs with between 6 months and 12 years’ experience. Subjects performed one maximal roundhouse kick on Thai pads. Three-dimensional analyses were enabled with Qualisys motion capture system. The speed of the heel immediately before impact is the most influential factor in producing a high velocity roundhouse kick. A significant and positive correlation between thigh length (r=0.647, P=0.009), shank length (r=0.984, P=0.003) and final heel velocity was found. The maximum linear velocity at any joint immediately before impact was found in the heel which was in accordance with the hypothesis. However, the summation of forces was not evident in this study. The speed of the heel is dependent on the speed of the knee and the length of the shank. This data suggests that athletes with greater thigh length, and more importantly, shank length may have a mechanical advantage in martial arts kicking over participants with shorter measures and may wish to begin training in Muay Thai or another striking art. This finding may also be advantageous for talent identification scouts.
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Contents Page
Title Page
Statement of Originality
Acknowledgements
Abstract
Contents
List of Figures
List of Tables
Chapter one – Introduction
1.1 Introduction
1.2 Aims
1.3 Hypothesis/Research Questions
1.4 Delimitations
1.5 Limitations
1.6 Definition of Terms
Chapter Two – Literature Review
2.1 Introduction to the Literature
2.2 Kinematics
2.3 Kinematics Data Collection
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2.4 Anthropometry and Talent Identification
2.5 kicking literature - General
2.6 Kicking Literature – Martial Arts
2.7 Kicking Kinematics
2.8 Summary
Chapter Three – Method
3.1 Participants
3.2 Equipment
3.3 Protocol
3.4 Data Analysis
Chapter Four - Results
4.1 Table 1 -
Chapter Five - Discussion
Chapter Six – Conclusion
Reference List
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Appendices
Appendix One – Warm up
Appendix Two - NHANES III anthropometric measures protocol
Appendix Three – Subject data
Appendix Four – Subject one Pelvis angles
Appendix Five – Subject one Pelvis angular velocity
Appendix Six – Subject one Linear Velocities of the Kicking Leg
Appendix Seven - Subject one Linear Velocities of Right Arm
List of Tables
Table No.
1 Final linear velocities of the joints of the kicking leg
2 Total duration of each phase of the kick
3 Correlations of the kinematic variables
Figure No.
1 Camera Set up
2 Average linear velocities of the kicking leg
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3 Mean Joint Contributions of the Kicking Leg
4 Average linear velocities at the joints of the right arm
5 Angular velocity at the pelvis
6 Angles at the Pelvis During Kick
7 Deterministic model of a roundhouse kick
8 Print screen of the XY, YZ and XZ axis
1.1 Introduction
Muay Thai is a combative sport in which competitors punch, kick, knee, elbow
and grapple their opponents. Professional male and female fighters compete in
5 rounds of 3 minutes with a two minute break between rounds. Fights are
decided by knockout or by the three umpires in accordance with a point system
(Delp, 2004). The roundhouse kick is considered a fundamental weapon in
Muay Thai which targets the side of the head, jaw, shoulders, rib cage,
abdomen, or legs of the opponent (Ruerngsa et al. 2000). Data shows that the
force generated by a kick in "Thai Boxing" can easily cause neurological
damage, skull fractures, facial bones and ribs (Sidthilaw, 1997).
According to official Muay Thai rules (muaythaionline, 2012), some of the best
scoring techniques in Muay Thai include knocking an opponent to the floor with
a concussive blow, unbalancing an opponent with kick and immediately
following with a strong striking technique, knocking an opponent off their feet
with a kick and landing an attacking technique that results in an opponent
turning their back on the attacking boxer. Therefore, kicks are the primary
attacking skills used in Muay Thai as the target area for kicking is larger (legs,
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torso, arms and legs), legs are longer than arms and can therefore reach
further, and kicking transfers a greater impact to the opponent than punching.
The roundhouse kick is one of the most frequently used foot skills in
Taekwondo sparring matches because of its usefulness in attack and counter-
attack, short execution time, and high chance to score (Kim et al., 2010). In
fighting conditions at high standards of competition, the speed of kicks plays a
crucial part in successful attacks (Pozo et al., 2011).
Falco (2009) simply describes the roundhouse kick as a multi-planar skill,
starting with the kicking leg travelling in an arc towards the opponent, keeping
the knee in a chambered position. The knee is extended in a snapping
movement, striking the opponent with metatarsal part of the foot extended.
When Kim et al. (2010) studied the effects of target distance on pivot hip, trunk,
pelvis, and kicking leg kinematics in Taekwondo roundhouse kicks, they divided
the body into four parts for ease of analysis: kicking leg, support leg, pelvis, and
upper body. The kick was then described in more detail: The centre of mass of
the kicking foot travels linearly in a semi-circular fashion to the target. The
support leg serves as a fulcrum or pivot hip while the kicking leg performs the
kick. The upper body is utilised as a counter-movement tool and aids in balance
while the pelvis acts as a convergence point for this to take place. The linear
motion of the pivot hip, angular motion of the pelvis about the pivot hip and
angular motions of the kicking leg joints combined create the linear velocity of
the kicking foot. The trunk counters the angular motion of the pelvis and kicking
leg for both linear and angular equilibrium.
Ascertaining which factors are important in developing high velocity kicks will
enable fighters and coaches to establish training programs that centre around
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these factors. This information can assist with the design of training
programmes based on quantitatively determined factors which equate to a high
velocity kick. Recognition of these factors can aid coaches in the development
of technique-orientated drills, which may speeding up the learning process.
(Shan and Westerhoff, 2005).
There is evidence of Muay Thai being practiced as early as 1781 (Ruerngsa et
al. 2000) and so Muay Thai and many other martial arts appear to be very
traditional in their approach, and have not been biomechanically analysed as
often as many other modern sports. Technology is now beginning to play a
considerable role in assisting martial artists to gain an advantage in training and
in competition (Pearson, 1997). Muay Thai is rapidly increasing in popularity
and has an estimated one million participants worldwide (Gartland et al., 2001).
As Muay Thai raises its profile, demonstrated by the birth of the Muay Thai
Premier league and by its popularity in mixed martial arts, it should be studied
more scientifically. The Muay Thai roundhouse kick has acquired minimal
recognition in scientific research to date which is surprising given the role it
plays in combat sports.
1.2 Aims
The aims of this study were to;
a) Ascertain whether or not the summation of speed is evident in the Muay Thai
roundhouse kick
b) Determine the kinematic variables that are most closely related to a high
velocity roundhouse kick.
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c) Investigate the correlation between anthropometric data and kick velocity.
d) Develop a deterministic model in order to depict all of the mechanical factors
that determine velocity in a Muay Thai roundhouse kick.
1.3 Hypothesis
a) The maximum linear velocity at the hip will precede the maximum linear
velocity at the knee and the maximum linear velocity at the knee will precede
the maximum linear velocity at the heel. Peak velocity at the ankle will be
greater than that of the knee and peak velocity of the knee will be greater than
that of the hip.
b) The greatest angular velocity and linear velocity at any joint in any limb will
be seen at the pelvis during phase one of the kick and at the heel immediately
before impact respectively.
c) There will be a significant positive correlation between limb/segment length
and kick velocity.
d) Length of the thigh and shank will be important factors in determining the
velocity of the Muay Thai roundhouse kick.
1.4 Delimitations
The subjects used in this study were 6 males who trained at “Hybrid
MMA” in Plymouth, Devon were able to attend UCP Marjon, Plymouth at
the allocated time.
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Subjects were asked to attend the testing session at the sports
laboratory, UCP Marjon, Plymouth.
Subjects underwent a standardised dynamic warm up typical of a Muay
Thai class in order to replicate training and competition.
Only the 4th kick that the subjects performed was analysed.
Two Thai pads were held as a target for the kick. The height and
distance of these pads were at the subjects’ discretion.
Kinematic data was acquired using videography collected by Qualisys
Motion Capture System.
Knee and heel angular velocity was not measured
1.5 Limitations
Moderating variables were not monitored. Day of the week, time of day,
daily activities, training schedule and diet were not noted.
Subjects movement before the heel left the ground and recovery phase
were not analysed.
Left foot and left hand placement were not analysed.
The sample size was relatively small
Subjects were of mixed ability and experience levels
Due to the complex movement of the kick and the relatively low number
of cameras, not all reflective markers could be captured in all frames.
1.6 Definition of Terms
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Muay Thai: a combative sport in which competitors punch, kick, knee,
elbow and grapple their opponents.
Taekwondo: a form of unarmed self -defence which focuses on
kicking techniques.
Final heel velocity: the velocity of the heel immediately before impact
Chapter Two – Literature Review
2.1 Introduction to the Literature
The aim of the literature review is to display the literature relevant to the present
study and to highlight gaps in the research. An overview of general kinematics
will be presented which looks at analysing methods and the development of the
deterministic model used for qualitative analysis. An overview of anthropometry
and talent identification will then look at how anthropometric measures may or
may not have an effect on physical performance and how this information can
be used in the process of talent identification. General kicking literature and
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martial arts kicking literature will be analysed before discussing kicking
kinematics, kinematics data collection and the summation of speed. The main
points from the chapter will then be summarised.
2.2 Kinematics
To understand the sources of motion of a Muay Thai kick, a method for
describing motion is required. “The term “kinematic” is used to describe the
study of motion with no regard to its cause” (Chapman, 2008 p15) and is one of
the most basic types of analyses that may be conducted because of this. To
make the study of movement easier, movements are classified as either linear,
angular or both (general) (McGinnis, 2005). A kinematic analysis describes the
positions, velocities and accelerations of bodies in motion (Hammil and
Knutzen, 2009). Two things are necessary for motion to occur: space and time
– space to move in and time during which to move (McGinnis, 2005).
Linear kinematics can be defined as straight line motion which occurs when all
points on a body or an object move the same distance over the same time
(Hamill and Knutzen, 2009). Displacement is the straight line distance in a
specific direction from starting position to final ending position. Displacement is
a vector quantity; this means it has a size associated with it as well as a
direction. “Velocity (which is also a vector) is displacement of an object divided
by the time it took for that displacement” (Hammil and Knutzen, 2009 p308-
315).
The subset of kinematics that deals with angular motion is angular kinematics.
Angular motion occurs when all parts of a body move through the same angle
but do not undergo the same linear displacement (Hammil and Knutzen, 2009).
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Angular displacement can be defined as the change in the angular position or
orientation of a line segment. Angular velocity is calculated as the change in
angular position or the angular displacement, that occurs during a given period
of time and angular acceleration is the rate of change in angular velocity, or the
change in angular velocity occurring over a given time.
The roundhouse kick starts in the sagittal plane and finishes in the transverse
plane because the target has a vertical surface that is perpendicular to the
ground. The roundhouse kick appears to involve motion in more than one plane
which makes three-dimensional analysis essential (Pearson, 1997).
2.3 Kinematics Data Collection
The recording of human movement in sport can be formally stated as: to obtain
a record that will enable the accurate measurement of the position of the centre
of rotation of each of the moving body segments and of the time lapse between
successive pictures (Bartlett, 2007). Despite kicking being three-dimensional in
nature, most kinematic research conducted has been recorded using two-
dimensional aparatus (Lees and Nolan, 1998).
The main method currently used for recording and studying sports movements
is digital videography. One of the strengths of videography is that it enables the
investigator to record sports movements not only in a controlled laboratory
setting, but also in competition. Advanced measurement systems and analytical
techniques have been frequently used to further the understanding of kicking
and the factors that influence kicking performance (Lees, 2010). Three-
dimensional analysis can also provide enlightenment on normative
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characteristics which are generally evident in highly-skilled athletes (Shan and
Westerhoff, 2005).
There are many benefits of using three-dimensional recording and analysis as
opposed to two-dimensional. Three-dimensional recording analysis has more
complex experimental procedures and can show the body’s true three-
dimensional movements. It requires less digitising time and has fewer
methodological problems, such as the transformation of coordinates from the
video image to the ‘real world’ movement plane. Three dimensional analyses
also allow angles between body segments to be calculated accurately, without
viewing distortions. It also allows the calculation of other angles that cannot, in
many cases, be easily obtained from a single camera view. One example is the
horizontal plane angle between the line joining the hip joints and the line joining
the shoulder joints, which can be visualised from above even if the two cameras
were horizontal. Finally, it enables the reconstruction of simulated views of the
performance other than those seen by the cameras (Bartlett, 2007).
A deterministic model can assist in the understanding of the kinematic factors
involved in a Muay Thai roundhouse kick. It is a model that determines the
relationships between an outcome and the biomechanical factors that produce it
(Hay & Reid, 1988a). Hay (1984) states that a deterministic model should have
two distinguishing features. First, the model is made up of mechanical quantities
or appropriate combinations of mechanical quantities. Secondly, all the factors
included at one level of the model must completely determine the factors
included at the next highest level. It is this second feature that leads us to refer
to these types of models as deterministic models.
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Hay and Reid (1988a) described the steps in developing a deterministic model;
the first step is to identify the primary goal, result/outcome of the performance to
be investigated. The outcome of a performance can be an objective measure
(e.g. distance, height, time, etc.) or a subjective measure (e.g. points awarded
in gymnastic and diving competition). The next step is to identify those factors
that produce the result. The factors included in the model should normally be
mechanical quantities wherever possible and each factor should be completely
determined by those factors that are linked to it from below. Hay and Reid
(1988b) also stated that this type of analysis aims to supplement whatever
experience the sport scientist or coach might have and to channel or direct the
analysis in a logical, systematic fashion, eliminating the risk of overlooking
influential factors.
In a review of the use of the deterministic model written by Chow and Knudson
(2011) it was summarised that the deterministic model approach provides a
strong theoretical or mechanical platform to examine the importance of various
factors that influence the outcome of a movement. Studies which have used
these models in biomechanics demonstrate their applicability in depicting
important mechanical criterion in human movement. However, Glazier and
Robins (2012) have since critically analysed the aforementioned paper and
concluded that although deterministic models may provide a useful starting
point for sports biomechanists examining the mechanical aspects of athletic
performance, they have inherent weaknesses that limit their practical
application. Specifically, their inability to provide substantive information about
coordinative movement patterns or ‘technique’ suggests that sports
biomechanists must explore alternative paradigms and theoretical frameworks if
17
they are to fulfil their main aims of improving performance and reducing injury
risk.
Once the relationships between a movement outcome and the biomechanical
factors that produce it have been defined, training strategies can be adopted by
the coach to develop these components. For instance, if the linear velocity at a
certain joint in a particular phase of the kicking motion was found to be
important, then specific technical work or strength and conditioning
programming can be employed to attain the desired adaptation.
2.4 Anthropometry
Anthropometry is the study of the measurement of bone, muscle, and adipose
tissue in the human body (NHANES III 1988). The field of anthropometry
encompasses a variety of human body measurements. Weight, stature
(standing height), recumbent length, skinfold thicknesses, circumferences
(head, waist, limb, etc.), limb lengths, and breadths (shoulder, wrist, etc.) are
examples of anthropometric measures.
The height and body size of an individual represents a factor that is generally
believed to affect the outcome of physical tests (Jaric, 2003). Indeed, some
authors often report data normalised for body size, rather than non-normalised
results. This may suggest that anthropometric variables could be a prediction of
performance.
The ability of a fast bowler to attain greater ball release speeds has been
suggested to be related to a bowler’s anthropometry (Glazier et al., 2000;
Portus et al., 2000; Stockill &Bartlett, 1996). Junior international fast bowlers
have slower ball release speeds than senior international fast bowlers due to
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longer upper limb lengths and higher angular velocities of the humerous
(Stockill and Bartlett, 1994). In this study ball release speed positiveky
correlated with total arm length (860 ± 36 mm; r = 0.583, P < 0.05), suggesting
that the most influential factor was radial length. Glazier et al. (2000) studied the
anthropometric and kinematic influences on release speed in mens fast-medium
bowling and found that angular velocity of the bowling humerus had a poor
correlation with ball release speed. It was also concluded in this study that
radial length was the dominant factor due to high correlations between ball
release speed and total arm length. It was found that a measurement of 0.1m at
the radial segment lead to a speed increase of 3.3m/s. Therefore, a more
efficient proximo-distal transfer should occur when a greater speed at this
segment is reached.
Van den Tillaar and Ettema (2004) conducted a study measuring the
relationship between maximum isometric strength and maximum velocity in
overarm throwing for male and female experienced handball players. Results
showed a significant and positive correlation between maximal isometric
strength and throwing velocity in men (r=0.43, P=0.056) and women (r=0.49,
P=0.027). Vila et al.(2009) studied the relationship between anthropometric
parameters and throwing velocity in water polo players and found significant
(p˂0.05) and positive correlations between throwing velocity and BMI (r=0.477),
flexed arm girth (r=0.479) and femur breadth (r=0.572). Factors influencing ball
throwing velocity in young female handball players was investigated by
Zapartidis et al. (2009) where it was found that throwing velocity significantly
(p< 0.05) and positively correlated with body height (r=0.335), arm span
(r=0.340), hand length (r=0.288) and hand spread (r=0.368).
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In contrast, Skoufas et al. (2004) found that throwing velocity is not correlated to
the body height (r=0.236, p=0.073) and the arm and forearm length were not
significantly correlated to the throwing velocity (r=0.167, p=0.206 and r=0.256,
p=0.051, respectively) when exploring the relationship between the
anthropometric variables and the throwing performance in handball. However,
arm span (r=0.342, p=0.008), length of hand (r=0.331, p=0.010) and width of
hand (r=0.390, p=0.002) significantly and positively correlated to throwing
velocity. Therefore, in this study, the last segment in the chain (the hand) had
the most influence on throwing velocity.
2.5 General kicking literature
In general, data is predominantly related to the kicking leg (Lees et al., 2010),
but other limbs are receiving more attention in the literature (Scurr and Hall,
2009; Bezodis et al., 2009; Ball, 2008; Shan and Westerhoff, 2005). Ball (2008)
considered the biomechanics of distance kicking in Australian rules football and
found that the foot speed and shank angular velocity to be 26.4 m/s and 1676°/s
respectively. Foot speed is significantly higher than that found in Dorge et al.
(2002) study where values of 18.6 m/s were recorded in experienced football
players. However, shank angular velocity at ball contact was similar in both
studies; 1676°/s in Australian rules football and 1610°/s in the experienced
soccer players. According to Ball (2008), the major contributor to maximal
kicking distance was greater foot speed and large shank angular velocities at
ball contact
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Foot velocities in soccer kicking have been recorded at 23.6m/s using a three-
dimensional cinematographic technique at 200 Hz (Nunome et al., 2006). Dorge
et al., (2002) reported that the velocity of the foot is a product of the linear
velocity of the knee and the angular velocity of the shank. Results from this
study show that the angular velocity of the shank was not at its maximum at the
moment of impact. Therefore, the linear velocity of the centre of mass of the
foot is the best measure of the success of a kick. Nunome et al., (2006)
suggests that there is a strong link between foot swing velocity and ball velocity
in soccer. This implies that to achieve maximal performance, the energy that
has been developed should not be reduced prior to ball contact. Dorge et al.
(2002) did, however, report a reduction in angular and/or linear velocity of the
kicking leg immediately before ball impact.
The measurement of three-dimensional kinematics of the upper extremity has
generally not received as much scientific attention as that of the lower limb (Rab
et al., 2002). There is a growing consensus that kicking foot velocity is the result
of actions of the whole body (Lees et al., 2010). Only one study (Shan and
Westerhoff, 2005) has used full-body three-dimensional motion capture and
modelling to examine kicking. The results of this study revealed that movement
of the upper body contributed considerably to skill effectiveness. It was also
concluded that a skilled player will rotate the trunk and extend and abduct the
arm on the non-kick side in order to form a tension arc at the beginning of the
step. The trunk flexors, hip flexors and quadriceps lengthen before their
contraction due to conditions provided by the tension arc. The use of the
stretch-shortening cycle in this instance should potentially create larger muscle
forces which may increase the effectiveness of the kick.
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Actions in soccer such as free kicks, goal kicks, penalty kicks and instep kicks
often involve kicking with the arm swaying. Swaying the non-kicking side arm
when running up to the ball may provide more strength to the kick due to the
muscle pre-lengthening and stretch of the swaying arm (Shan and Westerhoff,
2005). Ashby and Heegaard (2002) report that arm swaying motion is used to
maintain balance and increases the velocity of the body’s centre of gravity in
order to improve standing long jump performance.
This literature suggests that in sports such as soccer and rugby, the greatest
velocity at the most distal segment (the foot) results in the greatest ball velocity.
The movement of the upper body may also considerably contribute to skill
effectiveness.
2.6 Martial arts kicking Literature
Sorenson (1996) states that in order to determine the contribution of each joint
velocity to the final velocity (in this case the heel) of a specific movement, it is
necessary to study the total duration of the movement. A study by Falco et al.,
(2009) reviewed the total duration of the Taekwondo roundhouse kick in elite
and non-elite male athletes and found a mean time of 0.38 (+0.27) seconds
while Tang et al., (2007) found mean values of 0.6 (+.068) seconds and Boey
and Xie (2002) reported a mean time of 0.33 seconds.
Interestingly, reaction time needed to start a counterattack movement or to
avoid the attack has been reported by Vieten et al. (2007) at 0.34seconds. This
is the only study of its kind and could be considered vital when assessing the
total time taken to perform a roundhouse kick; if a kick takes more than
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0.34seconds then it is entirely possible for the opponent to have begun a block,
counter attack or an evasive move in order to avoid the strike. It has been
suggested that there several blocks (Delp, 2004) and techniques in which to
counter attack a roundhouse kick (Ruerngsa et al. 2000; Delp, 2004) including
the roundhouse kick itself (Demeere, 2009). To investigate this theory further an
analysis of the duration of the recovery phase (the point of impact to the point at
which the kicking leg returns to the floor) of the roundhouse kick needs to be
conducted to assess the extent at which the boxer is vulnerable.
Boey and Xie (2002) carried out a study investigating the turning kick
performance of Singapore National Taekwondo players. This study broke down
the kick into time taken between lifting the heel and max speed of hip (0.19
secs), max speed of the hip and max speed of knee (0.28), and max speed of
knee and max speed of foot (0.07 secs). However, “speed” and “velocity” were
used interchangeably in this study so it is unclear whether the distance between
foot and target was divided by distance (speed) or displacement (velocity).
Research carried out by Tang et al., (2007) on the kinematics of target effect
during roundhouse kick, the mean maximum velocity for the ankle, knee and hip
joint was 14.3m/s, 8.1m/s and 3.8m/s respectively. Pearson (1997) carried out a
similar study which investigated the kinetics and kinematics of the Taekwondo
turning kick where linear velocities of the ankle, knee and hip joint immediately
before impact were recorded at 12.1m/s, 2.11m/s and 0.69m/s respectively.
Similarly to Dorge et al., (2002), Sidthilaw (1996) also found that the linear
velocity of the ankle in the Muay Thai roundhouse kick reached the maximum
velocity (7.1 m/s) at 0.48 seconds prior to the point of impact. This reduction in
23
linear velocity of the ankle joint has been attributed to placing a greater
emphasis on accuracy (Pearson, 1997).
Only the kicking leg in Muay Thai has been observed (Sidthilaw, 1997),
however, the kicking leg and trunk (Kim et al., 2010), kicking leg and supporting
leg (Chang et al., 2007) and kicking leg and torso (Tsai et al., 2007) have been
examined in other studies in order to assess other contributions in the
Taekwondo roundhouse kick.
Literature is yet to include analysis of arm placement in martial arts kicks. Arm
placement in the Muay Thai roundhouse kick may not be taught to be placed in
the most desired or biomechanically advantageous position as in soccer or
rugby due to the combative nature of the sport i.e. the need to protect against
attacks from opponents. However, as stated by Demeere (2009) and Ruerngsa
et al. (2000), arm placement during the Muay Thai roundhouse kick is not
restricted to one position only and may be adapted to suit different situations
and desired outcomes. An investigation into arm placement during the Muay
Thai kick is required in order to ascertain whether or not one of these
adaptations result in a greater velocity kick.
2.7 Kicking Kinematics
The roundhouse kick appears to use the summation of speed theory in which
several segments of the body are involved in developing maximal speed. Welch
et al. (1995) briefly summarized this theory as ‘large base segments "passing"
momentum to smaller adjacent segments.’ The reactive impulse created by limb
movement can be quantified by either a direct measurement of impulse using
dynamography, or by an indirect measurement of the system's momentum
24
using kinematic analysis (Newton's Second Law) (Lees and Barton, 1996). But
the basic principle is that a system of segments moving at a certain velocity has
momentum. When a large base segment decelerates, the velocity of the
remaining system increases as it assumes the momentum lost by the base
segment. When one segment reaches its maximum angular velocity (zero
acceleration) during the midrange of its motion, it decelerates and transfers
angular momentum to the next adjacent distal segment in the chain (Welch et
al. 1995).
This sequence occurs, link by link, from large to small, from proximal to distal
until the end of the chain is reached (Kreighbaum and Barthels (1985),
therefore, the total speed is a sum of the total individual muscles added
together. Consequently, a large part of a Thai boxer’s mechanical performance
is derived from maximizing the kinetic link parameters.
Pearson (1997) studied this sequence in the Taekwondo turning kick and
concluded that practitioners should emphasise the sequential proximo-distal
sequencing, starting with flexion and abduction of the hip, and finishing with
knee extension. A pilot study by Sorensen (1996) shows this sequencing
occurring between the foot and knee in the martial arts high front kick. Sidthilaw
(1996) saw the same trend when investigating the kinematics of a roundhouse
kick using three-dimensional videography. Results showed that, in all subjects,
peak angular velocity at the hip preceded the peak angular velocity at the knee.
However, there are many other factors which contribute to creating maximal
velocity of a kick such as torso, arm and supporting leg positioning. Kim (1996)
found that hyperextension, abduction, and external rotation of the hip joint occur
prior to the kicking leg toe leaving the floor. Internal rotation and abduction of
25
the hip reached their peak during impact. Pearson (1997) stated that, when
analysing video data, the summation of speed sequence appears to begin with
trunk rotation.
2.8 Summary
Numerous studies have focused on the kinematics of kicking in field sports and
martial arts such as Taekwondo but a relatively small number have focused on
the kicking in Muay Thai. Kinematics is used to describe the study of motion
with no regard to its cause. A Muay Thai roundhouse kick involves all three
planes of motion which requires three dimensional analyses using digital
videography. A deterministic model can assist in the understanding of the
kinematic factors involved in a Muay Thai roundhouse kick and is a model that
determines the relationships between an outcome and the biomechanical
factors that produce it. Literature in soccer and rugby kicking has focused on
linear and angular velocity of the foot at ball contact. The measurement of
three-dimensional kinematics of the upper extremity has not received as much
scientific attention as that of the lower limb even the upper body also affects the
kicking performance.
Literature on martial arts kicks has focused on total duration, mean linear
velocity of joint segments and linear and angular final velocity of the kicking leg.
There is a lack of research analysing the torso and arms even though this may
affect kicking performance. The summation of speed is a theory in which
several segments of the body are involved in developing maximal speed and
may be evident in the Muay Thai roundhouse kick.
26
Chapter 3 - Method
3.1 Participants
The subjects used for this study were 6 Muay Thai practitioners recruited from
‘Hybrid MMA’ gym, Plymouth. Subjects mean age was 24.1 (4.2) yrs with
between 6 months and 12 years’ experience. Subjects took part in 3 technical
training sessions a week and did not take part in any type of strength and
conditioning programme. One of the subjects had fought in a professional
competition and all others had competed in local interclub competitions. All
subjects were informed of the complete protocol along with all the risks involved
in partaking in such activities. They had sufficient opportunity to ask questions
before signing medical screening form and an informed consent form.
3.2 Equipment
Qualisys motion capture systems
Qualisys Track manager
6 cameras (Proreflex MCU 240, Gothenburg, Sweden)
Tripods (Manfrotto 161MK2B)
Muay Thai pads (Twins Special, Size L - 20x41x6cm)
Tanita scale (model BC 418 MA)
Vertical ruler
27
Tape measure
3.3 Protocol
Anthropometric data (weight , standing Height, sitting Height, Buttocks [Hip]
Circumference, upper Leg Length, knee Height, upper Arm Length) were
measured in accordance with the National Health and Nutrition Examination
Survey III (NHANES III, 1988) protocols (appendix 2).
To obtain 3-dimensional data the Qualisys motion capture system was utilised.
The set up consisted of 6 cameras (Proreflex MCU 240) operating at 60hz
mounted onto tripods (Manfrotto 161MK2B) roughly 2.5m tall but were adjusted
in order to capture the whole movement. Cameras one and four were placed
directly in front (camera one) and behind (camera four) the subject at a distance
of 4.3m and 3.6m respectively from the subjects nearest foot. Cameras two and
three were positioned to the left of the subject at a distance of 2.4m and 3.6m
respectively and cameras five and six were positioned in a similar fashion at a
distance of 2.3m and 3.8m respectively (figure 1). An area of –x—x-- was
marked out for the subjects to stand and perform the kick.
28
Figure 1 – Camera set up
Reflective markers were placed on the appropriate bony landmarks (right
shoulder, elbow wrist, left and right hips, lumbar spine, cervical spine (C7), right
knee and heel) of the subject to make analysis of the movement possible (figure
2). It should be noted that a marker was not placed on the toe as with most
other martial arts kick studies because the shank of the kicking leg should make
contact with the opponent – not the foot. Also, a marker was placed on the heel
so it was evident when the heel left the ground which makes analysis more
accurate. The subject then stood in the marked area and performed a kick to
ensure the cameras picked up all of the reflectors. Cameras were then adjusted
as need be and when satisfactory the Qualysis wand was then used to calibrate
the equipment. The cameras were then set at 60 frames per second for ease of
data analysis later on.
Figure 2 -
29
Subjects were bare-foot and wore Muay Thai shorts and a vest to perform the
kick. A warm up typical of a Muay Thai session was performed by the subject
consisting of dynamic stretching, prehab exercises and ‘fire up’ drills exercises
was performed by each subject to help prevent injury and prepare the individual
for the kick (appendix 1). The subject stood on a mat to perform the kick in an
attempt to replicate training and, to an extent, fighting conditions as some
friction is required in order to pivot on the ball of the foot of the standing leg
while still remaining balanced. Thai pads were held by a trainer for the subject
to kick. The distance these pads were held away from the subject was at the
subjects’ discretion (Pearson, 1997) as this distance will vary from fighter to
fighter due to height, limb length, stance and fighting style. The subject then
performed one maximal roundhouse kick.
Joint angles, linear velocity of all landmarks previously mentioned were then
analysed using Qualysis track manager. Angular velocity of the pelvis was also
analysed. The distance between the foot of the subject and the target was
measured from the ankle joint to the rear Thai pad as the shin should make
contact with the opponent in a real match – not the foot. This data was then
opened in Microsoft Excel and mad into graphs for analysis.
3.4 Data Analysis
Linear velocity and angular velocity was calculated via Qualisys track manager
and analysed in Microsoft in Excel. Pearson’s correlation co-efficient was
implemented to determine correlation between each of the kinematic and
anthropological variables. Results were considered statistically significant if the
30
‘p’ value was less than 0.05 (P ˂ 0.05). All data was analysed using SPSS
version 19.0.
Chapter Four – Results
For ease of analysis the kick has been broken down into 3 phases; phase 1 is
defined as the moment the heel lifts off of the floor (heel off) to the maximum
linear velocity of the hip. Phase 2 is defined as the point of maximum linear
velocity of the hip to maximum linear velocity of the knee. Phase 3 is defined as
the point of maximum linear velocity of the knee to maximum linear velocity of
the ankle.
4.1
Table 1 - Final Linear Velocities of the Joints of the Kicking Leg
subject Hip Knee Heel
m/s m/s m/s
Mean (±S.D.) 1.1(±0.4) 2.6(±1.3) 13.6(±2.3)
maximum 1.6 3.7 16.7
31
minimum 0.7 0.3 10.9
Mean final velocities for all joints of the kicking leg in table 1 show that the most
distal joint (Heel) was travelling at the greatest velocity at the moment before
impact (13.6m/s [±2.3]), followed by the more proximal joints (knee) (2.6m/s
[±1.3]) and then the hip (1.1 [±0.4]).
4.2
Table 2 - Total Duration of Each Phase of the Kick
Subject
PHASE 1 - Lifting heel -
max Velocity of hip (sec)
PHASE 2 - Max Velocity of Hip - Max Velocity of
Knee (sec)
PHASE 3 - Max velocity of Knee - Max Velocity of Heel (sec)
Total Duration (sec)
Mean (±) 0.03(±0.03) 0.15(±0.05) 0.28(0.12) 0.35(0.07)
Maximum 0.08 0.23 0.43 0.42
Minimum 0.00 0.10 0.13 0.27
Table 2 shows that phase 3 of the kick took the longest duration (0.28s [0.12]),
followed by phase 2 (0.15 [±0.05]) and then phase 1 (0.03 [±0.03]).
4.3
32
Figure 2 – Average Linear Velocities of the Kicking Leg
Figure 2 shows time taken to perform the kick expressed as a percentage is
displayed along the horizontal axis. Linear velocity is measured in metres per
second and is displayed along the vertical axis. Each phase of the kick is
highlighted as blue shading and is labelled either phase 1, phase 2 or phase 3.
Standard deviation is displayed via the error bars which are coloured in
accordance with the line colour of the joint velocity being displayed. The starting
velocity of the knee and ankle both precede the hip, although, during the third
phase of the kick the velocity of the Heel does increase rapidly as the knee
decelerates which suggests that the proximo-distal segment sequencing is
present. Another characteristic of figure 3 is that the knee and hip joints actually
increase in velocity during the last 10 and 15% after steadily decreasing since
the beginning of phase two of the kick.
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
5
10
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75
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85
90
95
10
0
Lin
ear
Ve
loci
ty (
m/s
)
Time (%)
Average Linear Velocities of the Kicking Leg
Linear Velocity ofHip
Linear Velocity ofKnee
Linear Velocity ofHeel
PHASE 1 PHASE 2 PHASE 3
33
4.4
Figure 3 – Mean Joint Contributions of the Kicking Leg
Figure 3 shows joint velocity contributions of the kicking leg are expressed as a
percentage of total kick velocity in Figure 4. The maximum linear velocity at
each joint was calculated as a percentage of the linear final velocity at the heel
and is displayed along the vertical axis. Names of the joints are given along the
horizontal axis. The hip contributes 22% of the final heel velocity, the knee 31%
and the heel 49%.
0
5
10
15
20
25
30
35
40
45
50
Hip Knee Heel
Join
t Li
ne
ar V
elo
city
(%
)
Joint
Mean Joint Contributions of the Kicking Leg
Hip Knee
Heel
34
4.5
Figure 4 – Average Linear Velocities at the Joints of the Right Arm
Time taken to perform the kick expressed as a percentage is displayed along
the horizontal axis in figure 4. Linear velocity is measured in metres per second
and is displayed along the vertical axis. Each phase of the kick is highlighted as
blue shading and is labelled either phase 1, phase 2 or phase 3. Phase 2 shows
0.0
1.0
2.0
3.0
4.0
5.0
6.0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
10
0
Lin
ear
Ve
loci
ty (
m/s
)
Time (%)
Average Linear Velocities at the Joints of the Right Arm
Linear Velocity ofthe RightShoulder
Linear Velocity ofthe Right Elbow
Linear Velocity ofthe Right Wrist
PHASE 1 PHASE 2 PHASE 3
35
the greatest velocity in all joints in the right arm and phase 3 shows a gradual
decrease in all joints. The graph does not demonstrate the summation of speed.
4.6
Table 3 – Correlations of the Kinematic Variables
Height
Thigh
Length
Shank
Length
Maximum
Hip
Velocity
Maximum
Knee
Velocity
Final
heel
Velocity
Height Correlation 1 .887* .973** .570 .858* .959**
Significance
.018 .001 .238 .029 .003
N 6 6 6 6 6 6
Thigh
Length
Correlation .887* 1 .821* .370 .825* .920**
Significance .018
.045 .470 .043 .009
N 6 6 6 6 6 6
Shank
Length
Correlation .973** .821* 1 .697 .892* .954**
Significance .001 .045
.124 .017 .003
N 6 6 6 6 6 6
Maximum
Hip
Velocity
Correlation .570 .370 .697 1 .595 .588
Significance .238 .470 .124
.213 .220
N 6 6 6 6 6 6
Maximum
Knee
Velocity
Correlation .858* .825* .892* .595 1 .962**
Significance .029 .043 .017 .213
.002
N 6 6 6 6 6 6
Final heel
Velocity
Correlation .959** .920** .954** .588 .962** 1
Significance .522 .003 .009 .003 .220 .002
N 6 6 6 6 6 6
36
Statistical significance was calculated using a 2-tailed T-test and was deemed
to be statistically significant if the result was ˂ 0.05 (*) or ˂ 0.01 (**). All data
was analysed using SPSS. A significant and positive correlation exists between
thigh length (r=0.920, P=0.009), shank length (r=0.954, P=0.003), subject
height (r=0.959, P=0.003) and final heel velocity.
4.7
Figure 5 – Angular Velocity at the Pelvis
-300.0
-200.0
-100.0
0.0
100.0
200.0
300.0
400.0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
10
0
An
gula
r V
elo
city
(D
eg/
s)
Time (%)
Angular Velocity at the Pelvis
Average angular Velocityat Pelvis (YZ)
Average Angular Velocityat Pelvis (XZ)
Average Angular Velocityat Pelvis (XY)
PHASE 1 PHASE 2 PHASE 3
37
Angular Velocity at the hips along the YZ, XZ, XY axis (see Figure 8) is shown
in figure 5. Time taken to perform the kick expressed as a percentage is
displayed along the horizontal axis. Angular velocity is expressed as degrees
per second and is displayed along the Vertical axis. Angular velocities are
erratic throughout the movement and fluctuate at each stage. Phase 3 shows a
sharp increase in angular velocity in the YZ axis while the XZ and XY show a
steady decrease.
4.8
38
Figure 6 – Angles at the Pelvis During Kick
Angles at the hip joint throughout the entire kick along the YZ, XZ, XY axis (see
Figure 8) are shown in figure 6. Time taken to perform the kick expressed as a
percentage is displayed along the horizontal axis. Angular velocity is expressed
as degrees per second and is displayed along the Vertical axis. YZ pelvis angle
decreases smoothly throughout phase 1 and 2 before steadily increasing in
phase 3. XZ and XY pelvis angles steadily increase during phases 1 and 2, XY
continues to increase before plateauing and decreasing while XZ gradually
decreases.
Chapter 5 - Discussion
The main findings in the present study are that the speed of the heel during the
3rd phase of the kick appears to be the most influential factor in producing a
high velocity roundhouse kick and thus shank length is the most advantageous
-10.0
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
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0
An
gle
(d
eg)
Time (%)
Angles at Pelvis During Kick
Pelvis Angle(XY)
Pelvis angle(XZ)
Pelvis Angle(YZ)
39
anthropometric measure to possess. These findings are consistent with the
hypothesis that thigh length and shank length will be important factors in
determining the velocity of a roundhouse kick. The speed of the heel is
dependent on two things; the speed of the knee and the length of the shank.
Seeing as the linear speed of the knee joint is the sum of the linear speed of the
hip joint and the product of the angular speed at the hip and the length of the
thigh, it seems advantageous for Thai boxers to possess long thighs and long
shanks. However, due to the summation of speed theory, shank length appears
to be more pertinent to a high velocity kick due to each distal segment
assuming the proximal segment’s velocity.
In order to depict the crucial factors that contribute to a high velocity
roundhouse kick, a deterministic model was developed. This model will
establish the mechanical factors that determine the velocity of a roundhouse
kick.
Velocity of the Roundhouse
Kick
Displacement (shank to
target)
Length of Lower Limbs
Time (shank to
target)
Speed of heel
40
Velocity is speed in a given direction. In this case, the velocity is being analysed
as opposed to speed as the fighter needs to make contact with the target
(opponent) as quickly as possible so velocity gives a better indication of
efficiency. The displacement between shank and target depends on the lower
limb length of the subject. A fighter should utilize the space between himself
and his opponent efficiently to enable him to stay at a safe distance from his
opponent i.e. out of punching and kicking range but where he doesn’t have to
move an unnecessary distance to be able to attack. The time taken for the
shank to reach the target depends on the speed at which the heel travels from
the floor to the target.
The speed of the heel immediately before impact is the product of the knee joint
linear speed and shank length. The linear speed at the knee is the function of
Speed of heel
Speed of Knee
Speed of HipLength of
ThighAngular Speed
at Hip
Phase 1 Change in
Angular Speed
Phase 2 Change in
Angular Speed
Length of Shank
41
the linear speed at the hip and the sum of the thigh length and hip angular
speed.
42
Figure 7 – Deterministic Model of the Roundhouse Kick
Velocity of the Roundhouse kick
Displacement (shank → target)
Length of lower limbs
Time
(shank → target)
speed of heel
speed of knee
speed of hip
length of thighangular speed of
hip
phase 1 change in angular speed
phase 2 change in angular speed
length of shank
43
The importance of shank length is evident when analysing correlations between
the different kinematic variables and final heel velocity. A significant and
positive correlation exists between thigh length (r=0.647, P=0.009), shank
length (r=0.984, P=0.003) and final heel velocity in the present study which is
consistent with the hypothesis. This could be attributed to the summation of
speed theory as the limb rotating around the axis (joint) has more time to gain
momentum which is then passed on to the next distal segment. A stronger
correlation exists between shank length and final heel velocity as, in theory, the
speed accumulated by the 3rd phase would be greater than in the 1st or 2nd
phase so therefore, the segment (shank) rotating around the axis (knee joint)
should have the potential to gather more momentum. This is in accordance with
Skoufas et al. (2004) who also found that the most distal segment in the chain
had the most influence on throwing velocity.
Generally speaking, when a segment is rotating, the longer the segment, the
higher the linear velocity developed on the distal to the centre of rotation side.
When applying this principle to a Muay Thai roundhouse kick, athletes with
longer segments should develop higher throwing velocity of the ball provided
that the angular velocities around the participating to the motion joints are not
lower when compared to the angular velocities of an athlete with shorter
segments (Skoufas et al., 2004)
Maximum hip velocity positively correlated (r=0.595) with maximum knee
velocity. This correlation was not significant (P=0.213); although it may suggest
that the large base segment (hip) could possibly have transferred momentum to
the smaller adjacent segment (knee). The knee, however, demonstrates this
sequence to a much larger extent with a significant (P=0.002) and almost
44
perfect positive correlation (r=0.962) between maximum knee velocity and final
heel velocity. This data, once again, suggests that there was a bigger
contribution from the hip flexors and knee extensors during the kick and little hip
extensor/torso rotator activation. Figure 4 displays this evidence more clearly;
the hip joint accounts for 22% of the total velocity during the kick, the knee
accounts for 31%, and the heel 49%. This demonstrates the relatively low
contribution of the hip. However, no known studies have dissected the
roundhouse kick in this way which makes comparisons impossible.
A significant (P=0.003) and positive correlation (r=0.959) was found between
final heel velocity and subject height which are similar to findings by Van den
Tillaar & Ettema (2004), Vila et al. (2009), Zapartidis et al. (2009) and Skoufas
et al. (2004) who recorded significant and positive correlations between ball
velocity and anthropometric variables such as body mass index (BMI), body
mass, lean body mass and height in throwing tests. In the present study, subject
height was measured but seated height and limb length was not. Therefore, this
finding cannot be attributed to either leg length or torso length. Skoufas et al.
(2004) found that arm length was less important than hand width and hand
length when producing a high velocity throw. If torso length positively correlated
with final heel velocity then this may have suggested that the proximal-distal
segment sequencing began with torso rotation. However, this seems unlikely
given that maximum hip velocity does not significantly correlate with maximum
knee velocity or final heel velocity.
Identifying the desired anthropometric variables required for Muay Thai
performance could lead to the discovery of potential performers and the
recognition of current participants with the potential to become an elite Thai
45
boxer. Talent detection refers to the discovery of potential performers who are
currently not involved in the sport in question while talent identification (TID) is
the process of recognising individuals currently participating in the sport with the
potential to become elite (Mohamed et al. 2009).
Height and length of limbs can largely effect sports performance (Hahn, 1990)
and, based on the evidence presented in the present study, could also influence
Muay Thai performance. Therefore, comparing height and limb lengths of
athletes to literature can assist in the TID process. For instance, Elite Australian
rowers have been reported as a tall group with proportionally long limb length
compared with the general population (Hahn, 1990).
TID and development has become a vital component of many sport
programmes (Falk et al., 2004) and, if introduced to Muay Thai, may be useful
by measuring thigh length and shank length in order to assess potential within
the sport. No literature currently exists on TID in Muay Thai. The introduction of
TID in Muay Thai would seem advantageous due to its recent raise in profile
and the role it currently plays in combat sports, as previously mentioned.
Table 2 gives the time taken for each phase of the kick to take place. A mean
time of 0.03 seconds was recorded for the lifting of the heel to reach maximum
velocity of the hip, 0.15 seconds for the maximum velocity of the hip to reach
maximum velocity of the knee and 0.28 seconds for maximum velocity of the
knee to reach maximum velocity of the hip. The total duration of the kick was
recorded at a mean value of 0.35 seconds which is similar to those found by
Boey and Xie (2002) who recorded times of 0.33 seconds which is surprising as
this study used more experienced athletes from the Singapore National
Taekwondo squad. The total duration of the kick in this study higher than that
46
found in Falco et al., (2009) study of non-elite athletes (0.23 secs) and much
lower than Tang et al., (2007) (0.6 seconds). The total duration of the kick
recorded in this study (0.35 seconds) is 0.01 seconds slower than the reaction
time needed to start a counterattack movement or to avoid the attack (Vieten et
al., 2007). This indicates that the opponent may have already begun a block,
counter attack or an evasive move in order to avoid the strike before the
roundhouse kick has landed. The recovery phase of the roundhouse kick needs
to be conducted to investigate this theory in full but from the evidence presented
it would seem that the mean total duration of the roundhouse kick performed in
this study would be too slow to be deemed an effective strike in a Muay Thai
fight.
Time taken from heel off until maximum hip velocity was much quicker in the
present study when compared to Boey and Xie, (2002) study (0.19 seconds),
while the second and third phase in the previously mentioned study (0.07, 0.07)
are much faster than in the present study (0.15, 0.28). This evidence suggests
that the fairly inexperienced Muay Thai practitioners used in this study didn’t
place much emphasis on the initial hip drive and, instead, focused more on the
knee flexion and then knee extension phases. Since the large base segments
pass momentum to smaller adjacent segments so that the smaller segment to
transfers momentum to the next adjacent distal segment in the chain, the
athletes in the present study are missing out on an opportunity to maximise
segment velocity to pas onto the next distal segment. The Singapore National
Taekwondo squad athletes used in the previously mentioned study took longer
to gain maximum velocity in order to transfer this momentum to the next two
47
phases of the kick and achieve a greater velocity at the moment before impact
(18m/s) than in the present study (13.6m/s).
The reason for the poor hip drive during phase 1 may be due to differences in
neural adaptation. Neural adaptation refers to changes in the nervous control of
the muscle (Adamson et al. (2008). Subject 6 (6 months experience) and
subject 1 (12 years’ experience) displayed a large difference in initial hip
velocity (1802m/s and 2851m/s respectively). The more experienced athletes
may be able to recruit more motor units and increased motor unit firing through
repetition; it has been suggested by Van Cutsem et al. (1998) that strength
training may increase motor unit firing frequency and thereby increase the
potential for force development. However, none of the participants in the
present study took part in a strength and conditioning programme at the time of
testing.
In contrast to the hypothesis, the average linear velocities presented in figure 3
do not strictly represent the summation of speed theory to full extent as seen in
other martial arts kick studies by Pearson (1997), Sidthilaw (1997) and
Sorensen et al., (1996). In these studies the maximum velocity of the hip
precedes the maximum velocity of the knee and the maximum velocity of the
knee precedes the maximum velocity of the ankle for every subject. However, in
the present study the starting velocity of the knee and heel both precede the
hip, although, during the third phase of the kick the velocity of the heel does
increase rapidly as the knee decelerates which suggests that the proximo-distal
segment sequencing is present.
Joris et al. (1985) found it most likely that proximal segment deceleration (in this
case, the knee) could be explained by Newton's third law, which states that a
48
more proximal segment's action on a more distal segment will cause an equal
but opposite directed reaction on the more proximal segment. Sorenson et al.
(1996) suggests that active deceleration of the thigh is likely to be performed by
the gluteus maximus or the hamstring muscles. It was therefore of particular
interest to determine the exact temporal activity of these muscles during the
movement.
Another characteristic of figure 3 which differs from the aforementioned studies
is that the knee and hip joints actually increase in velocity during the last 10 and
15% after steadily decreasing since the beginning of phase two of the kick. This
is an interesting finding as this has not been seen previously in martial arts kick
studies. The Muay Thai practitioners taking part in this study may be performing
a re-extension the of the hip and knee to help produce maximal velocity before
impact due to the fact that the initial hip extension during phase one was not
emphasised and, as a consequence, they didn’t achieve the velocity potential to
pass on to the next distal segment.
This increase in joint velocity in the latter stages of the kick is in contrast to the
results found by Sidthilaw (1997). In this study joint velocity actually decreases
by around 4m/s during the final 0.06 seconds of the movement on average. This
finding has been attributed to the subjects placing a greater emphasis on
maintaining accuracy (Pearson, 1997; Lees et al., 2010) and a protective
mechanism of the hamstrings which prevents the knee joint from reaching full
extension at full velocity (Lees et al., 2009) to avoid hamstring injury. However,
EMG readings would need to be analysed to explore this theory further.
Final heel velocity was recorded at 13.6m/s. This finding is consistent with the
hypothesis that the greatest linear velocity at any joint will be seen at the heel
49
immediately before impact. This data is substantially higher than that recorded
by Sidthilaw (1996) for the Thai boxing middle roundhouse kick which was
recorded at 7.1 m/s. As previously mentioned, all Thai boxing subjects in the
aforementioned study recorded their maximum ankle velocities approximately
0.10s before impact. The mean ankle heel velocities found in this study are
similar to those found in other martial arts kick studies - 14.3m/s (Tang et al.,
2007), 12.1m/s (Pearson, 1997) and significantly lower than that found in
studies by Kong et al., (2000) who recorded values of 18.83m/s and O’Sullivan
et al., (2009) who recorded values of 17.66m/s. It should be noted that the
majority of these studies recorded the final linear velocity of the foot/ankle and
not the heel.
Figure 5 shows the average linear velocities of the right shoulder, elbow and
wrist during the kick. Modeling of movement of the wrist and elbow is relatively
simple, since both can be represented as two-degrees-of-freedom joints.
However, the shoulder joint complex is an articulation that defies simple
kinematic description. It consists of two separate articulations, with
scapulothoracic and glenohumeral components (Rab, 2002).
The data suggests that the summation of forces theory is not evident during the
arm swing in the present study. Ruerngsa et al. (2000) states that because the
roundhouse kick relies on the rotation of the body it is easy for boxers to lose
their balance while attempting to deliver the kick. A common way to
compensate for this is for a boxer to drop his rear arm backwards and
downwards (extending the shoulder and elbow joints) in order to stay balanced.
Rapid acceleration of the wrist is evident during the hip and knee drive (phase 1
and 2) but rapidly decreases during phase 2. The large changes in linear
50
velocity at the wrist and the relatively low changes seen at the elbow and
shoulder joints suggests that the arm movement is predominated by extension
of the elbow. Although the ‘recovery’ phase of the kick wasn’t analysed in the
present study, not only does the arm-leg synchronisation appear to be an
important factor in recovering from impact but could also affect kicking velocity.
Ashby and Heegaard (2002) found increases of 12.7% in the take-off velocity of
standing long jumps due to arm motion. However, the standing long jump only
takes place in two planes of motion. It was concluded that the additional
momentum imparted to the system by swinging the arms may contribute to the
increase in take-off velocity. So, if swinging the arms in the same plane and
direction of force can add additional momentum then one would assume that
swinging the arms in the opposite direction would decrease the momentum
carried across each phase.
This counter productivity can be seen in figure 5 as the linear velocities of the
right shoulder, elbow and wrist begin to decrease after phase 1 of the kick. This
decrease in velocity could be attributed to the R.O.M. at the shoulder joint; the
decrease in shoulder, elbow and wrist velocity begins just after phase one of the
kick so from this point onwards the lack of flexibility in the shoulder joint appears
to be pulling the torso and lower body in the opposite direction which could be
decreasing the velocity in the heel. However, accurate determination of
scapular position is difficult without skeletal pins, time-consuming palpation, or
complex imaging techniques that are potentially invasive, expensive and
impractical in most research settings (Rab, 2002).
Demeere (2009) and Ruerngsa et al. (2000) agree that swinging the right arm
backwards and downwards at the same time helps stabilise the kick by giving
51
counterbalance for the hip turn. Demeere (2009) also lists other advantages to
this technique such as protection of the chin by pulling the rear shoulder into the
jaw and the fact that this is the easiest and most natural movement when
performing the kick. However, this publication by Demeere (2009) offers an
alternate right arm position for the Muay Thai roundhouse kick; extending the
arm towards the face of the opponent. One of advantages of this method is that
if the opponent’s eyes are covered it will make it harder for him to see and to
counter strike, giving a window of opportunity to land the kick. Another
advantage is that the arm can be used to punch at the same time and can also
disguise the kick and, finally, the arm can be placed diagonally across the
opponent’s body to smother his arms or use it to sweep the opponents legs
from under him with the kick.
Ruerngsa et al. (2000) also advocates the use of this ‘arms up’ method and
concludes that the roundhouse kick may be performed with both fists held to the
front in order to protect the face. Using this alternate method may decrease kick
velocity to a lesser extent due to the kicker being able to increase momentum
using the arm. However, the precise mechanisms by which arm swing can
cause greater kick velocity are still unclear and these methods need to be
compared and analysed fully in order to ascertain the advantages and
disadvantages associated with each technique. This analysis should include a
recovery phase as Ruengsa et al., (2000) states that the reason the arm is
dropped is because it is easy for boxers to lose their balance while attempting
to deliver the kick. Therefore, analysis of the recovery phase would show
whether dropping the arm is an effective technique to use during a real fight.
52
The left arm was not analysed in the present study. Ruengsa et al., (2000)
states that the left (lead) arm move in front of the face in a high guard position
that places the elbow near jaw level and the hand practically above (but in
contact with) the head. This creates a more solid barrier of defence against a
counter attack. The shoulder of the arm that is dropped protects the jaw on the
other side as previously mentioned. Demeere (2009) also approves of this left
hand placement but also advocates the option of bringing the hand across the
body and in front of the face in order to protect the chin from straight punches to
a greater extent.
Shan and Westerhoff (2005) studied full body kinematics in soccer and found
that the upper body demonstrates some important characteristics of technique.
The non-kicking side arm was found to abduct and horizontally extend before
support foot contact and then adduct and horizontally flex to ball contact and
has been frequently attributed to the maintenance of balance (Lees et al.,
2010). If this is the natural placement of the left arm then Thai boxers are
somewhat restricted when placing the left arm on the head and may have to
balance themselves in different ways such as throwing the right arm down and
back as previously mentioned.
53
Figure 8 – A print screen of the XY, YZ and XZ axis.
Rotational movement can be explained by means of the following 3 axes (figure
8): the longitudinal (Z) axis (axis of rotation passing from feet to head through
the centre of gravity, the lateral (X) axis (axis of rotation passing from right to
left through the system’s centre of gravity), and the frontal (Y) axis (axis of
rotation passing from front to back through the system’s centre of gravity). With
the definition of the 3 principal axes, a description of combined movements may
be possible (Schack, 2003).
During phase 1 the pelvis shows little increase in angular movement (2.6°) in
the XY axis with an increase from 11.1°-13.7°. This angular movement could be
attributed to the initial abduction of the hip of the kicking leg and the forward
movement created by the triple extensors (extensors of the hip, knee and ankle)
of the supporting leg. During this phase the right hip is beginning to rotate
54
around the support or “anchor” leg via the XY axes. The angular velocity
recorded at the pelvis along these axes began at 13.1°/s at heel off and
increased by 10.2°/s before descending to 19.3°/s at the end of the phase. This
fluctuation of relatively low angular velocity may be attributed to irregular motor
unit recruitment and/or rate coding (Adamson et al. (2008) which may be
caused by fact that some participants were inexperienced practitioners.
Voluntary movements are planned, executed, and stored in memory directly by
means of representations of their anticipated perceptual effects. Cognitive
concepts seem to play a crucial role in movement control and representations
create a link between the central goal and the biomechanical organization of the
movement (Schack, 2003). Rotational movements such as the roundhouse kick
demand a highly defined perceptual-cognitive organization and a mastering of
many degrees of freedom. By using an expert-beginner paradigm, differences in
the structure and organization of knowledge between experts and beginners in
physical activity were found (Thomas and Thomas, 1994). It was concluded that
experts have far superior skills, declarative knowledge, and procedural
knowledge in performance; the latter is the one which has the greatest potential
for manipulation.
A sharper increase (10.9°) was seen in the XZ axis where the hip of the kicking
leg is elevated along the vertical (Z) axis via the triple extension mechanism. In
order for the right hip to rotate around the support leg it must first be elevated
along the Z axis via the triple extension mechanism described earlier with the
addition of the hip abductors again, accounting for the movement along the X
axis. Angular velocities along the XZ axis followed the same trends as XY axis
with a fluctuation of relatively low velocity.
55
The Linear and vertical (YZ) angle decrease (-8.3°) of the pelvis during phase 1
of the kick could also be attributed to triple extension – but mainly the plantar
flexion of the ankle which is causing the pelvis to move in a linear direction as
well as in a vertical direction. Angular velocity begins at -127.4°/s and fluctuates
slightly in the same fashion as in the XZ and XY axis.
A steady and even increase in the XY and XZ planes is seen during phase 2.
The majority of the angular motion of the pelvis along the XY axis is achieved
during phase 2 and the angle at the XZ axis actually reaches its peak in the last
frame of the phase. This steady increase in pelvic angle is coupled with a
wavering decrease in angular velocity.
Phase 2 shows a steep but gradual angle decrease (58.6°) in the YZ axis. It is
during phase 2 that the majority of this angular change occurs in the YZ axis.
The athlete should only have the ball of his supporting foot in contact with the
ground in order to use this as a “pivot” (Ruerngsa et al., 2000) in which to
externally rotate the left hip in preparation for the later phases. It appears to be
this triple extension that is causing this pivot and the angular change in the YZ
(linear/lateral) axes. It seems reasonable to assume that the pivot takes place in
order for this change in angle to occur in the YZ axis considering that the
majority of the angular change for the XY and XZ also occurs in this phase.
Therefore, this pivot is making the rotation of the pelvis around the anchor leg
easier by having less mass in contact with the ground and thus, less friction. A
gradual increase in angular velocity of 42.9°/sec is seen before a slight
decrease of 4.7°/sec during the last 13% of the phase.
Pelvic angular change along the XY axis during phase 3 sees a much less
steep increase (10.1°) and eventually a decrease (3.3°) during the last 15% of
56
the kick. Phase 2 saw the angle along the XZ axis peak and then begin a
gradual decrease (17.3°) during phase 3. Angular velocities along the XY and
XZ axes fluctuate but are consistent with one another in that, an increase
occurs, followed by a decrease, another increase before ending with a gradual
decrease during the last 20% of the kick. This evidence suggests that there is
less emphasis being placed on hip abduction and triple extension to rotate the
pelvis, and when this information is considered along with the average linear
velocities of the ankle, there is evidence that the emphasis is has shifted to
knee extension to maximise ankle velocity immediately before impact. Pedzich
(2006) states that the use of hips allows an athlete to shorten the distance
between him and his opponent. It is assumed that this means that when a Thai
boxer increases the angle through the XY axis he is able to reach a greater
distance with the kick. This could be advantageous when avoiding a counter
attack.
The pelvic angle along the YZ axis decreases (7.8°) in phase 3 before
beginning a rapid increase (26.2°) during the final 25% of the kick. Angular
velocity along these axes rapidly increase for the first 8% of the phase before
decreasing slightly for 5%; this may suggest that one or all of the triple
extensors is flexing and then re-extending during this phase. The reason for this
may be to increase linear velocity of the heel immediately before impact. In
contrast to the hypothesis, YZ angular velocity, as with the YZ angle, then
rapidly increases to its peak value during the 3rd phase before decreasing
during the last 10% of the phase. This suggests that the majority of the activity
seen in the YZ axis occurs during the last 25% of the kick.
57
An interesting finding when comparing linear with angular change and angular
velocities is that the majority of the angular change and angular velocity at the
pelvis occurs during phase 2 where ankle linear velocity is relatively low. During
phase 3 the linear velocity of the ankle increases sharply while the XY and XZ
angular change and angular velocity at the pelvis decrease.
In future, studies should use professional athletes who have all competed at a
similar level.
Chapter 6 - Conclusion
In line with the hypothesis, thigh length and shank length were found to be
influential in the velocity of the Muay Thai roundhouse kick and significantly and
positively correlated with final heel velocity. In contrast to the hypothesis, the
summation of speed theory was not evident in the present study as maximum
velocity of the hip did not precede the maximum velocity of the knee and the
maximum velocity of the knee did not precede the maximum velocity of the heel
for any subject. Average knee linear velocity was higher than hip and heel linear
velocity throughout phases 1 and 2 which suggests hip flexion dominates during
these phases and not torso rotation or knee extension as in some other studies.
The maximum linear velocity at any joint immediately before impact was found
in the heel which was in accordance with the hypothesis.
This data suggests that athletes with greater thigh length, and more importantly,
shank length may have a mechanical advantage in martial arts kicking over
participants with shorter measures and may wish to begin training in Muay Thai
58
or another striking art. This finding may also be advantageous for talent
identification scouts.
Muay Thai boxers may wish to employ the following technical practical
applications:
Phase 1 - Begin the kick by emphasising hip flexion to increase maximum knee
linear velocity over phases one and two.
Phase 2 - Attempt to achieve maximal knee flexion during phase two in order to
achieve maximal heel final linear velocity.
Phase 3 - Emphasise maximal angular velocity and pelvis rotation during phase
3. Also, emphasise hip flexion and knee extension immediately before impact.
Note: Athletes may also wish to utilise the “arms up” method throughout the
kick.
Strength and Conditioning practical applications:
1. A strength training programme may be included in a Thai boxer’s
regime in order to potentially increase motor unit firing frequency and
thereby increase the potential for force development.
2. Specifically, hip flexion strength should be addressed; this movement
initiates the kick and is often overlooked in strength and conditioning
programs.
3. Open and closed kinetic chain exercises should be included in
programmes.
59
References
Adamson, M., MacQuaide, N., Helgerud, J., Hoff, J., Johan, O. (2008) Unilateral
arm strength training improves contralateral peak force and rate of force
development, Eur J Appl Physiol (2008) 103:553–559
Ashby, B. M., Heegaard, J. H. (2002) Role of arm motion in the standing long
jump, Journal of Biomechanics 35, 1631–1637
Ball, K. (2008): Biomechanical considerations of distance kicking in Australian
Rules football, Sports Biomechanics, 7:1, 10-23
Bartlett, R., (2007) Introduction to Sports Biomechanics Analysing Human
Movement Patterns, Second edition, Taylor & Francis Group, Oxon
Bezodis, N., Trewartha, G., Wilson, C., Irwin, G. (2007) Contributions of the
non-kicking-side arm to rugby place-kicking technique, Sports Biomechanics,
6:2, 171-186
Boey, L. W., Xie, W. (2002). Experimental investigation of turning kick
performance of Singapore National Taekwondo players. Proceedings of the
20th International Symposium on Biomechanics in Sport. Caceres, Spain, 302-
305.
Chang, W-G, Chang, J-S, Tang, W-T (2007), Kinematic and Kinetic Analysis of
Lower Limbs in Taekwondo Double Jump Roundhouse Kick During Landing,
60
Institute of Coaching Science, National College of Physical Education and
Sports, Taiwan.
Chapman, Arthur. E, 2008, Biomehanical Analysis of Fundamental Human
Movement, USA, Human Kinetics
Chow, J. W., Knudson, D. V. (2011): Use of deterministic models in sports and
exercise biomechanics research, Sports Biomechanics, 10:3, 219-233
Delp, C. (2004) Muay Thai: Advanced Kickboxing Techniques, 1st ed. USA:
Frog, Ltd.
Demeere, W. (2009) [Online]: The Leg Kick: Your guide to using the shin kick in
the ring or the cage, accessed 06.05.2012, available at:
http://users.telenet.be/wim.demeere/The-Leg-Kick-A-guide-for-Devastating-
Low-Kicks-in-MMA-and-muay-Thai.pdf
Dorge, H.C., Andersen, T.B., Sorensen, H. and Simonsen, E.B. (2002)
Biomechanical differences in soccer kicking with the preferred and the non-
preferred leg. Journal of Sports Sciences 20, 293-299.
Falco, C. A., Alvarez, O. B. C., Castillo, I. C., Estevan, I. A., Martos, J. D.,
Mugarra, F. D., Iradi, A. E. (2009) Influence of the distance in a roundhouse
kick’s execution time and impact force in Taekwondo, Journal of Biomechanics
42, 242–248
Falk, B., Lidor, R., Lander, Y., Lang, B. (2004): Talent identification and early
development of elite water-polo players: a 2-year follow-up study, Journal of
Sports Sciences, 22:4, 347-355
Gartland, S., Malik, M. H. A., Lovell, M. E. (2001) Injury and injury rates in Muay
Thai kick boxing, Br J Sports Med, 35:308–313
Glazier, P. S. and Robins M. T. (2012) Comment on “Use of deterministic
models in sports and exercise biomechanics research” by Chow and Knudson
(2011), Sports Biomechanics, 11:1, 120-122
Glazier, P. S., Paradisis, G. P., Cooper, S-M (2000) Anthropometric and
kinematic influences on release speed in men’ s fast-medium bowling, Journal
of Sports Sciences, 2000, 18, 1013-1021
Hahn, A. (1990) (cited in Hoare and Warr, 2009) Identifcation and selection of
talent in Australian rowing. Excel, 6, 5-11
Ham, D. J., Knez, W. L., Young, W. B. (2007) A Deterministic Model of the
Vertical Jump: Implications for Training, Journal of Strength and Conditioning
Research, 21(3), 967-972
61
Hamill, J. and Knutzen, K. M. (2009): Biomechanical Basis of Human
Movement, Lippincott Williams & Wilkins,
Harun, H., Xiong, S. J., Pendidikan, F. (2012) The Symmetry In Kinematics
Between The Dominant And Non-Dominant Legs In Taekwondo Turning Kick
Universiti Teknologi, Malaysia (online) accessed 09.01.2012, unpublished,
http://eprints.utm.my/10720/1/The_Symmetry_In_Kinematics_Between_The_Do
minant_And_Non.pdf
Hay, J.G. and Reid, G. (1982) (cited in Lees, 2002) Anatomy, Mechanics and
Human Motion. Englewood Cliþs, NJ: Prentice-Hall.
Hay, J. G. (1984) [cited in Chow and Knudson (2011)] The development of
deterministic models for qualitative analysis. In R. Shapiro, and J. R. Marett
(Eds.), Proceedings of the Second National Symposium on Teaching
Kinesiology and Biomechanics in Sports (pp. 71–83). Colorado Springs, CO:
United States Olympic Committee.
Hay, J. G., and Reid, J. G. (1988a) Anatomy, mechanics and human motion.
Englewood Cliff, NJ: Prentice-Hall.
Hay, J. G., and Reid, J. G. (1988b) [cited in Ham et al., 2007] Anatomy.
Mechanics, and Human Motion, Englewood Cliffs. NJ: Prentice Hall
Hoare, D. G. and Warr, C. R. (2000): Talent identification and women's soccer:
An Australian experience, Journal of Sports Sciences, 18:9, 751-758
Jaric, S. (2003) Role of body size in the relation between muscle strength and
movement performance. Exercise Sport Sci Rev 31:8–12
Jöris, H.J., van Muyen, A.J., van Ingen Schenau, G.J. and Kemper, H.C. (1985)
(cited in Sorenson et al., 1996), Force, velocity and energy flow during the
overarm throw in female handball players. Journal of Biomechanics, 18, 409-
414
Kreighbaum, E. & Barthels, K.M. (1985) (cited in Kim, 1996). Biomechanics: A
qualitative approach for studying human movement. Minneapolis, MN: Burgess
Publishing Company
Kim, J. W., Kwon, M. S., Yenuga, S. S., Kwon, Y. H., (2010) The effects of
target distance on pivot hip, trunk, pelvis, and kicking leg kinematics in
Taekwondo roundhouse kicks, Sports Biomechanics, 9(2): 98–114
Kim, Y., (1996) Effect of Practice on Pattern Changes: Roundhouse Kick in
Taekwondo, Master of Science, Korea: Korea Advanced Institute of Science &
Technology
62
Kong, P-W., Luk, T-C. and Hong, Y. (2000) Difference Between Taekwondo
Roundhouse Kick Executed by the Front and Back Leg – A Biomechanical
Study, The Chinese University of Hong Kong, Hong Kong SAR, 268-272
Lees, A and Barton, G (1996): The interpretation of relative momentum data to
assess the contribution of the free limbs to the generation of vertical velocity in
sports activities, Journal of Sports Sciences, 14:6, 503-511
Lees, A. (2002): Technique analysis in sports: a critical review, Journal of
Sports Sciences, 20:10, 813-828
Lees, A., and Nolan, L. (1998). The biomechanics of soccer: A review. Journal
of Sports Sciences, 16, 211-234.
Lees, A., Steward, I., Rahnama, N. and Barton, G. (2009) Lower limb function in
the maximal instep kick in soccer, Contemporary Sport, Leisure and
Ergonomics, Taylor and Francis, 148-160
Lees, T. Asai, T. B. Andersen, H. Nunome and T. Sterzing (2010): The
biomechanics of kicking in soccer: A review, Journal of Sports Sciences, 28:8,
805-817
McGinnis, P. M. (2005), Biomechanics of sport and exercise 2nd edition, p48
Mohamed, H., Vaeyens, R., Matthys, S., Multael, M., Lefevre, J., Lenoir, M. and
Philippaerts, R. (2009): Anthropometric and performance measures for the
development of a talent detection and identification model in youth handball,
Journal of Sports Sciences, 27:3, 257-266
Muay Thai Online (2012): Muay Thai Judging. [ONLINE] Available at:
http://www.muaythaionline.org/features/muaythaijudging.html. [Accessed 03
March 12].
Nhanes III (1998) National Health and Nutrition Examination Survey III, Body
Measurements (Anthropometry), (ONLINE) accessed 26.02.2012
Nunome, H., IkegamI, Y., Kozakai, R., Apriantono, T., Sano, S. (2006)
Segmental dynamics of soccer instep kicking with the preferred and non-
preferred leg, Journal of Sports Sciences, 24:05, 529-541
O’Sullivan, D., Chung, C., Lee, K., Kim, E., Kang S., Kim, T. and Shin, I. (2009)
Measurement and comparison of Taekwondo and Yongmudo turning kick
impact force for two target heights. Journal of Sports Science and Medicine 8,
13-16
Pearson, J. N., (1997). Kinematics and Kinetics of the Taekwondo-Do Turning
Kick. Bachelor of Science, New Zealand: University of Otago
63
Pedzich, W., Mastalerz, A., Urbanik, C. (2006) The comparison of the dynamics
of selected leg strokes in taekwondo WTF, Acta of Bioengineering and
Biomechanics Vol. 8, No. 1,
Pieter, F. and Pieter (1995), speed and force in selected Taekwondo
techniques, Biology of Sport v.12 (4), p. 257-266, Accessed 08.03.2012 (online)
http://books.google.co.uk/books?hl=en&lr=&id=cRp91zZJHLIC&oi=fnd&pg=PA2
57&dq=+Reaction+time+in+Taekwondo&ots=Wsm6XnSimZ&sig=3eS4jkSKlbljZ
Cuyx7EbiVkiFyE#v=onepage&q=Reaction%20time%20in%20Taekwondo&f=fal
se
Portus, M. R., Sinclair, P. J., Burke, S. T., Moore, D.J.A., and Farhart, P.J.
(2000): cricket fast bowling performance and technique and the influence of
selected physical factors during an 8-over spell, Journal of Sports Sciences,
18:12, 999-1011
Pozo, J., Bastien, G., Dierick, F. (2011) Execution time, kinetics, and kinematics
of the mae-geri kick: Comparison of national and international standard karate
athletes, Journal of Sports Sciences, 29:14, 1553-1561
Rab, G., Petuskey, K., Bagley, A. (2002) A method for determination of upper
extremity kinematics, Gait and Posture 15, 113–119
Ruerngsa, Y., Charuad, K. K. and Cartmell, J. (2000) Muay Thai: The Art of
Fighting (online), accessed 06.04.2012, available at:
http://www.singto.co.uk/Techniques/artoffightingebook.pdf
Schack, T. (2003): The relationship between motor representation and
biomechanical parameters in complex movements: Towards an integrative
perspective of movement science, European Journal of Sport Science, 3:2, 1-13
Scurr, J. and Hall, B. (2009) The effects of approach angle on penalty kicking
accuracy and kick kinematics with recreational soccer players, Journal of Sports
Science and Medicine (2009) 8, 230-234
Serina, E.R., and Lieu, D.K. (1992) (cited in Harun, 2012) Thoracic injury
potential of basic competition taekwondo kicks. Journal of Biomechanics,
24(10), 951-960
Shan, G. and Westerhoff, P. (2005): Soccer, Sports Biomechanics, 4:1, 59-72
Sidthilaw, S, 1996. Kinetic and Kinematic Analysis of Thai Boxing Roundhouse
Kicks. Ph.D.. Oregon State: Oregon State University
Skoufas, D, & Katzamanidis, C., Hatzikotoylas, K., Bebetsos, G., & Patikas, D.
(2004). The relationship between the anthropometric variables and the throwing
performance in handball.
64
S⊘rensen, H., Zacho, M., Simonsen, E. B., Dyhre‐Poulsen, P., Klausen, K.
(1996): Dynamicsof the martial arts high front kick, Journal of Sports Sciences,
14:6, 483-495
Stockill, N.P. and Bartlett, R.M. (1994) (cited in Glazier et al., 2000) An
investigation into the important determinants of ball release speed in junior and
senior international fast bowlers. Journal of Sports Sciences, 12, 177-178
Stockill, N.P. and Bartlett, R.M. (1996). Possible errors in measurement of
shoulder alignment using 3-D cinematography. In Proceedings of the XIVth
International Symposium on Biomechanics in Sports (edited by J.M.C.S.
Abrantes), pp. 209± 212. Portugal: Edi‡ï es FMH.
Tang W.T, Chang J.S and Nien Y.H. (2007). “The Kinematics of Target Effect
During Roundhouse Kick in Elite Taekwondo Athletes.” Journal of
Biomechanics. 40(S2), XXI ISB Congress 59
Thomas, K. T., Thomas, J. R. (1994): Developing expertise in sport: The
relation of knowledge and performance. International Journal of Sport
Psychology, Vol 25(3), 295-312
Tsai, Y. J., Huang, C. F., Gu, G. H. (2007) The kinematic Analysis of Spin-Whip
Kick of Taekwondo in Elite Athletes, Poster Session 1/Sport. 14:45-15:45
Van Cutsem M, Duchateau J, Hainaut K (1998) (cited in Adamson et al., 2008):
Changes in single motor unit behaviour contribute to the increase in contraction
speed after dynamic training in humans. J Physiol 513:295–305
Van den Tillaar, R., and Ettema, G. (2004). Effect of body size and gender in
overarm throwing performance. European Journal of Applied Physiology, 91,
413–418.
Vieten, M., Scholz, M., Kilani, H., Kohloeffel, M. (2007) Reaction time in
Taekwondo. In: Proceedings of the 25th International Symposium on
Biomechanics in Sport. Ouro Preto, Brazil
Vila, H., Ferragut, C., Argudo, F..M., Abraldes, J. A., Rodriguez, N., & Alacid, F.
(2009). Relationship between anthropometric parameters and throwing velocity
in water polo players. Journal of Human Sport and Exercise, 4, 57–68.
Welch, C. M., Banks, S. A., Cook, F. F., Draovitch, P., (1995) Hitting a Baseball:
A Biomechanical Description, Journal of Orthopaedic and Sports Physical
Therapy, 22: 5
Zapartidis, I., Skoufas, D., Vareltzis, I., Christodoulidis, T.,Toganidis, T., &
Kororos, P. (2009). Factors influencing ball throwing velocity in young female
handball players. Open Sport Medicine Journal, 3, 39–43.
65
Appendix One – Warm up
2 mins - Jogging on spot
10x body weight squats
10x body weight walking lunges with torso twist
10x standing lateral lunges
10x A skip
10x Frankenstein walks
10x knee hug/quad stretch (hold each for 1 second)
10x walking glute med stretch
10x arm swing forward
10x arm swing back
30 secs – monster walks with thera band
10x glute bridges
10x (each leg) donkey kicks
66
Appendix Two - NHANES III anthropometric measures protocol
67
Appendix Three – Subject Data
Subject Age Exp. Standing Height
Mass Segment Lengths (m)
(yrs) (yrs) (m) (kg) shank thigh
1 27 12 190 87 0.45 0.44
2 23 8 185 80 0.44 0.44
3 19 0.5 180 78 0.43 0.4
4 20 0.8 175 86 0.42 0.4
5 26 9 186 82 0.44 0.44
6 30 1 183 79 0.43 0.43
68
Appendix Four – Subject one Pelvis Angles
NO_OF_FRAMES 19 NO_OF_CAMERAS 6 NO_OF_MARKERS 9458732 FREQUENCY 60 NO_OF_ANALOG 0 ANALOG_FREQUENCY 0 DESCRIPTION --
TIME_STAMP 2012-03-05, 13:48:57
DATA_INCLUDED Angle MARKER_NAMES Angle_YZ Angle_XZ Angle_XY
Frame Time Angle_YZ Angle_XZ Angle_XY
239 3.98333 78.408 3.299 11.1
240 4 75.286 8.903 11.619
241 4.01667 70.071 14.17 13.72
242 4.03333 64.092 19.035 16.902
243 4.05 57.397 24.381 20.261
244 4.06667 50.269 29.192 24.402
245 4.08333 41.787 34.388 29.13
246 4.1 32.651 39.546 33.431
247 4.11667 22.883 42.853 38.424
248 4.13333 12.274 44.824 42.584
249 4.15 5.5 43.468 46.005
250 4.16667 0.581 39.955 50.039
251 4.18333 -1.912 36.899 53.034
252 4.2 -2.299 35.155 54.747
253 4.21667 -0.61 34.892 55.102
254 4.23333 3.258 34.274 55.527
255 4.25 8.957 32.401 56.082
256 4.26667 15.031 30.241 55.494
257 4.28333 20.85 27.73 54.138
69
Appendix Five – Subject One Pelvis Angular Velocity
NO_OF_FRAMES 19 NO_OF_CAMERAS 6 NO_OF_MARKERS 9458732 FREQUENCY 60 NO_OF_ANALOG 0 ANALOG_FREQUENCY 0 DESCRIPTION --
TIME_STAMP 2012-03-05, 13:51:47
DATA_INCLUDED Angular Velocity MARKER_NAMES Angular_Velocity_YZ Angular_Velocity_XZ Angular_Velocity_XY
Frame Time Angular_Velocity_YZ Angular_Velocity_XZ Angular_Velocity_XY
239 3.98333 -82.641 331.111 -4.281
240 4 -250.103 326.127 78.596
241 4.01667 -335.811 303.981 158.487
242 4.03333 -380.212 306.315 196.21
243 4.05 -414.693 304.683 224.981
244 4.06667 -468.295 300.211 266.08
245 4.08333 -528.54 310.646 270.884
246 4.1 -567.129 253.97 278.81
247 4.11667 -611.317 158.315 274.595
248 4.13333 -521.486 18.452 227.433
249 4.15 -350.779 -146.044 223.627
250 4.16667 -222.377 -197.068 210.882
251 4.18333 -86.411 -144.004 141.247
252 4.2 39.069 -60.238 62.023
253 4.21667 166.718 -26.434 23.415
254 4.23333 287.006 -74.721 29.427
255 4.25 353.183 -120.996 -0.984
256 4.26667 356.802 -140.12 -58.321
257 4.28333 321.453 -146.242 -92.721
70
Appendix 6 – Subject one Linear Velocities of the Kicking Leg
NO_OF_FRAMES 19 NO_OF_CAMERAS 6 NO_OF_MARKERS 9458732 FREQUENCY 60 NO_OF_ANALOG 0 ANALOG_FREQUENCY 0 DESCRIPTION --
TIME_STAMP 2012-03-05,
13:38:55 DATA_INCLUDED Velocity MARKER_NAMES right knee_vel
right hip_vel right heel_vel
Frame Time (secs)
Time (%) right hip_vel right knee_vel
right heel_vel
1 0 0% 2851 5915 5069
2 0.02 6% 2737 6539 6711
3 0.03 11% 2581 7186 7089
4 0.05 17% 2512 7729 6091
5 0.07 22% 2478 8152 5198
6 0.08 28% 2395 8273 5562
7 0.10 33% 2232 8562 6075
8 0.12 39% 2019 8093 6423
9 0.13 44% 1629
6635
10 0.15 50% 1236 6478 6771
11 0.17 56% 907 5125 6856
12 0.18 61% 577 3293 7051
13 0.20 67% 621 1926 7453
14 0.22 72% 787
8159
15 0.23 78% 781 1928 9095
16 0.25 83% 770 2359 10568
17 0.27 89% 844 2656 12310
18 0.28 94% 819 2924 14250
19 0.30 100% 822 3451 16661
71
Appendix 7 - Subject one Linear Velocities of Right Arm
NO_OF_FRAMES 19 NO_OF_CAMERAS 6 NO_OF_MARKERS 9458732 FREQUENCY 60 NO_OF_ANALOG 0 ANALOG_FREQUENCY 0 DESCRIPTION --
TIME_STAMP 2012-03-05, 13:45:44
DATA_INCLUDED Velocity MARKER_NAMES right shoulder_vel right elbow_vel right wrist_vel
Frame Time
right shoulder_vel
right elbow_vel
right wrist_vel
239 3.98333 1831.583 1598.863 3759.841
240 4 2207.775 1256.927 4189.002
241 4.01667 1795.055 1269.576 4439.89
242 4.03333 1376.995 1275.987 4887.694
243 4.05 968.641 1302.729 5232.552
244 4.06667 1049.581 1274.078 5383.952
245 4.08333 1294.106 1462.459 5498.85
246 4.1 1507.508 2089.485 5570.281
247 4.11667 1468.708 2718.998 5695.967
248 4.13333 1168.804 2773.823 5801.18
249 4.15 761.205 2765.227 5749.334
250 4.16667 455.596 3055.15 5395.163
251 4.18333 312.381 3317.005 4934.164
252 4.2 310.354 3206.485 4403.062
253 4.21667 391.985 2817.95 3812.292
254 4.23333 536.635 2461.09 3289.05
255 4.25 631.55 2220.424 2880.674
256 4.26667 680.337 1873.187 2515.791
257 4.28333 680.084 1445.926 2063.517
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