and Introduction only) Author Wai-Po Tang, Vol.1, n.3, 1999. Webpublish
Comparative Kinematics analysis of an expert-novice differences
in a Wing Chun Front Kick.
study investigates the kinematics parameters of a martial art (Wing
Chun style) front heel kick. The objectives are to establish a profile
expert-novice differences during three stages of the whole movement;
and to compare past research's findings of the proximal-distal theory
at the point of impact. Two dimensional videography (single camcorder)
was used to record the movement at a sports hall, and the data was
digitised, filtered and smoothed for further analysis. The subjects
are one male martial expert of 20 years experience and one male
novice with no previous martial art experience. The expert's kicking
movement took 0.54s, novice 0.76s, expert peak thigh angular velocity
-992.1502°/s vs novice -469.4301°/s, peak knee angular velocity
1476.7608°/s vs 763.4023°/s, peak ankle linear speed 13.4352m/s
vs 6.8171m/s. The findings supports previous research's theory of
proximal-distal effects on speed. Keywords: Wing Chun, front heel
kick, martial arts, kinematics, approach, release and recovery,
Wing Chun, front heel kick, martial arts, kinematics, approach,
release and recovery, impact.
and efficient principles of martial art kicks are often discussed
and instructed in clubs and via magazines. There are often debates
and claims that training in a particular martial art style will
improve kicking performance but mostly unsubstantiated. Recreational
practitioners, self-defence artists and sport competitors in martial
arts train with a different mentality, but a need in understanding
and applying efficient techniques.
is not much in depth scientific research on martial arts, and
most of it has been conducted on Karate (Japanese martial art) and
Tae Kwon Do (Korean martial art) but none at all for Wing Chun (Chinese
martial art style) techniques. Sorensen et al (1996:483) investigated
the dynamics of high front kick by filming 17 skilled subjects (Tae
Kwon Do practitioners) with a 50Hz 200 frames/sec high speed camera
(Teledyne DBM 45) and a electromyogram (EMG) recorded five major
muscle groups of the lower extremity. The subjects performed 3 high
kicks aimed at a suspended tennis ball at chin height. The fastest
trial was selected for analysis. The inquiry questioned what causes
the deceleration of the thigh when kicking, and whether active thigh
deceleration enhance the performance of the high front kick.
findings were conclusive that thigh deceleration was passive
and is caused by the lower leg acceleration and by a knee extensor.
It is not caused by active deceleration of the glutei or hamstring
muscles. Lees and Nolan (1998) reviewed the biomechanics of a soccer
kick and stated 'a large angular velocity of the shank (lower leg)
results in a high foot speed'. This clearly indicate the proximal
end of the leg velocity is paramount to the speed of the distal
end of the lower extremity. Wickstrom (1975) also suggested that
in a soccer instep kick, thigh angular velocity reduces when the
shank angular velocity increases up to impact with the ball; the
thigh becomes almost stationary at the point of impact.
(1988:185) stated, 'kicking involves the development of angular
momentum obtained as the product of a limb's angular velocity and
it's moment of inertia. The linear velocity of the kicking foot
is the product of the effective radius and the leg's angular velocity
at impact'. There does not appear an opposing argument to the proximal-distal
kicking theory, however, the previous research concentrated on the
relationship of the thigh and shank of a homogeneous group, but
no comparative research on the specificity of expert-novice differences.
examination of differences between two people who are already
skilled and those who are minimally skilled represents a relatively
new and rapidly growing area of individual-differences research
(Ericsson, 1996; Starkes & Allard, 1993). Considering the past research
investigated the kick at a certain phase of the movement, there
are many variables that would enhance successful in martial arts.
Wickstrom's Revised 4 Stage Model 3 Stage Model Backswing Approach
Pre-kick Step & backswing 1 1 Forwardswing Release Knee Lift Foot
lift & kick 2 2 Release Recovery Leg Rotation Leg Retract 3 3 Follow
Through 4 Figure 1.
of Wickstrom's 4 Stage Model and Revised 3 Stage Model. Kinematic
parameters of the Wing Chun's Front Heel Kick (FHK) are divided
into three stages so that specific primary variables are selected
for further analysis. Wickstrom (1975) stated four stages of a mature
kicking motion in football: 1) the withdrawal of the thigh and shank
during backswing; 2) the rotation of the thigh and shank forwards,
which occur as a result of hip flexion; 3) when the thigh angular
velocity reduces, there is a corresponding increase in shank angular
velocity up to impact with the ball; and 4) the follow through (Lees
and Nolan, 1997). These four 'stages' of the model are specific
to a soccer kick but do not consider the approach and recovery as
needed for martial art.
revise stage model needs to be constructed to allow for the
specific tactical requirements for martial art kicking technique.
This would be a three stage model (see figure 1): i) Approach as
from left toe-off to right thigh's backswing and right knee final
flexion (important to be discrete); ii) Release initial right knee
extension in the backswing phase to impact (important to be fast
& powerful); iii) Recovery as from impact to right foot departure
from target (important to avoid counter-attack).
subjects' kicks are recorded by a single video camera along
the sagittal plane that provided two dimensional data. The FHK movement
is in the sagittal plane about the transverse axis but the is some
degree of lateral rotation of the kicking leg in the transverse
plane about the vertical axis. However, the rotational magnitude
is relatively minimal and this study is focussed on broader variables.
Bartlett (1989) stated, 'The advantage of two dimensional cinematography
or videography is simplicity, but requires the movement to be in
a pre-selected movement plane and introduces perspective error for
non-planar movements; however, it yield acceptable results for essentially
research are concerned with kinematics of the FHK and not kinetics
or muscular activation, therefore, single camera can provide acceptable
two dimensional data. This study is aimed to establish a kinematic
profile of an expert Wing Chun practitioner and a novice kicking
characteristics. Comparative analysis will examine three stages
of the whole movement; approach (pre contact), flight and impact,
and post contact.
selected kicking technique of this investigation is the Front
Heel Kick (Cheen Jet Tek ). It is consider one of most practical
kicks in the Wing Chun style of martial art, whereby it is commonly
applied in contests. This kick is very similar to a footballer's
front instep kick and the Tae Kwon Do high front kick except that
the former uses the instep and the latter uses the ball of the foot
for initial collision; the type and height of the target is also
different. Therefore, the proximal-distal scalars and vectors are
comparable to past research on football skills or other similar
martial art kicks.
summary, the objectives are to establish an expert-novice profile
and compared the release phase to previous research. The research
kinematic parameters of the FHK are: the peak values; Approach-
angular velocities and displacement of the right thigh; Release-
the relationship of right thigh and right knee's angular velocity
against the right ankle's linear speed; Recovery- angular displacement
of right thigh and right knee against linear displacement of the