What techniques and
biomechanical principals might a netballer employ to increase the speed of a
‘chest pass’?
Introduction:
Netball, for many years now
is one of the most popular team sports in the world played by an estimate of 20
million people over the countries (International federation of netball
association, 2009). It has been stated that netball in Australia is the second
most popular organised recreational activities, therefore is a popular sport to
be taught by practitioners. The chest pass is the first pass, which will be taught
to use in netball, as it is the pass which is relied on and used the most as it
is the most accurate and controlled pass, especially for short distances.
Biomechanics has been defined as a study of movement with special emphasis on
human beings through the use of science of mechanics (Hatze, H.1975). Through the use of biomechanics we are
able to analyses and give reason for the skills output and what we may expect
or see as the end result of that specific skill. For example the netball chest
pass has a significant amount of intricate movements and factors, which
determine the speed, and accuracy of the ball. The chest pass in netball is one
of the passes, which is highly used, as it is seen to be the most efficient
pass. Therefore it is my understanding that there is a lot of biomechanics
behind a chest pass in order to produce the correct amount of speed needed to
make the intended distance and accuracy. Speed and accuracy of a chest pass is
significantly important, as they do not want their opponent to intersect the
pass. This blog will provide a guide of the important biomechanical factors a
chest pass involves.
The following video is a
detailed analysis of the key elements and biomechanics of a chest pass and how
to perform a chest pass, both basics and in a game situation. The main
techniques of a chest pass start with the positioning of the hands, then the
feet leading into the transformation of the weight from the back to the front
and the extension of the arms and wrists. The biomechanics principals behind a
chest pass are the kinetic chain movements required for the transformation of
weight from the proximal and distal end of the movement. The power and energy
needed to perform the chest pass is adequate as to generate a maximal force
behind the speed and to transfer weight from the back to the use of their
abdominal and arms requires energy.
Kinetic Chain:
For a successful implement of
a chest pass in netball all of the joints in the kinetic chain are required to
simultaneously move in a push-like movement patter (Blazevich. A. 2010. P.196).
A push-like movement pattern explains its self, as if we move like we are
pushing something (Blazevich. A. 2010. P.196). Due to all joints acting
simultaneously, the torque generated from each joint will provide an overall
high amount of force (Blazevich. A. 2010. P.196). The simultaneous joint
rotations of the kinetic chain often result in a straight t-line movement at
the end of the chain, which allows the athlete to achieve highly accurate
movements. As for in a netball pass positioning feet in a shoulder width
position, moving up to the transformation of the joints moving the upper body
from an up-right position forwards using the strength of the athletes
abdominal. Show below is an example of the transfer of the weight through the
use of the legs, transferring the weight from the back to the abdomen.
Image taken from: (http://www.talkbasketball.co.uk/guides/basketball_skills_passing.html,
2007)
How to achieve accuracy in a chest pass?
Push-like Movement Pattern:
A push-like pattern can be
applied to a chest pass in order to produce accuracy; however it needs to meet
a range of criteria’s. This is an example of the push-like movement used in a
chest pass how the symmetrical transfer of movement provides a high level of
accuracy.
Image Taken from: (Blazevich, 2010, p. 202.)
The movement pattern of the
chest passes needs to be effective through both of the movement stages, both
the closed kinetic chain and the open kinetic chain movements (Blazevich. A.
2010. P.197). As shown in the video above the chest pass’ initial movement
phase is to take a step forward with their preferred foot, creating a
generation of force and transfer starting at the proximal end of the kinetic
chain. Therefore the strength of the netballer’s legs and hip rotation is
important for this initial stage. Things like the leg press and the bench press
exercises are some exercises, which will target the closed end of the kinetic
chain joints. The dominant foot, which is in front, will be creating a
push-like pattern, as it will be holding the stance and keeping the body
grounded in order to generate and apply the force and transfer of the distal
end of the body.
What is the movement and structure
involved in a chest pass?
The most important aspects to
achieve an accurate chest pass is the structure of the body. The position of
the hips and shoulder trunk is crucial, as they need to be facing the desired
direction. The ball will leave the hands as to where the athletes shoulders and
hips are facing therefore it is important to have excessive movement in these
areas of the body, which can be influenced through the exercises stated above.
Therefore the strength within the hips and shoulders and abdominal can be crucial,
as it will identify the amount of force you are able to apply to the ball. Studies
suggest that individuals with greater relative lower body strength produce
higher magnitude through the planted food allowing them to modify their
positioning of their hips according to where they wanted the ball to go (Spiter T. Cochrane J. Hart N. Haff
G. & Nimphius S.2013)
How to generate increase the speed and
accuracy of a chest pass?
Through the extension of the
shoulders, elbows, wrists and fingers all tendons within, will significantly
recoil which increases the speed of the chest pass (Blazevich. A. 2010.
P.197-205). As the chest pass incorporated two hands it produces a symmetrical forward-directed
movement causing the ball to move in a relatively straight line (Blazevich. A.
2010. P.197-205). This is important as accuracy is netball is crucial as the
court area is relatively small therefore a chest pass can easily be intercepted
if the pass is not accurate. This stage of the chest pass incorporates a
throw-like movement pattern, which is still performed within the push-like
movement pattern. The push-like movement pattern is the initial stage of the
chest-pass, which leads into the throw-like movement pattern, when the ball is
being released through the extension of the upper body and distal joints of the
kinetic chain.
What momentum is required to step into a
chest pass?
Momentum summation of force:
Throughout the process of the
chest pass the body mass will start on the back foot generating to the front
foot as the arms and shoulders are extended to push the pass. Although a chest
pass allows the ball to travel at a higher force and accurately, the
generalisation of a push-like pattern of a pass generates a relatively low
movement speed. This is subject to the shortening of the muscle movement, as
the ball starts close to the chest to extend the arms to maximal extension
(Blazevich. A. 2010. P.197-205). In order to create momentum to our body for
the chest pass, it is initiated by the step forwards, then pushing the
shoulders rapidly forwards, simultaneous with the elbows moving outwards and
outwards while the hands on the ball staying close to the chest (Blazevich. A.
2010. P.197-205). From this is creates two important things, a significant
amount of momentum is generated for the upper body and arms, and forwards
velocity is generated. Mean while the tendons in the hands and fingers while
holding the ball are rapidly stretched, while the elbows are flexed outwards
causing the tendons to stretch as well (Blazevich. A. 2010. P.197-205). As
shown in the example below:
Image
taken from: (http://street-basketballss.blogspot.com.au/2012_09_01_archive.html.
2012).
This image emphasises the
movement of the arms, shoulders and fingers when performing a chest pass.
How else can we use this information?
The biomechanics of a chest
pass in netball it can be beneficial extended learning of other skills needed
within netball, such as an over arm pass, a bounce pass or even shooting for a
goal, as similar movements are produced. It could also enhance the results in a
game scenario are it may improve the accuracy and speed of the ball allowing
them to score easily or to keep position of the ball. As the chest pass adopts
the push-like movement pattern, it can be applied to other games, which require
a significant amount of accuracy and speed. The push-like throw pattern of the
kinetic chain would be beneficial for coaches who are focusing on basketball
shooting and or passing, as it is very similar to a netball chest pass.
Throwing a discus and javelin incorporates the kinetic chain biomechanical
principals, as there is rotation of the torso and accelerations of the arm. A
javelin throw requires a large amount of force and power being it to be able to
successfully throw it and to have an effective result.
The chest pass is commonly
used in the same context as netball in basketball. However the mass of the ball
is slightly heavier and the chest pass could be performed on the run, it still
incorporates a pus-like movement pattern and the transfer of body wait from the
back to the torso. It also includes the extension of the tendons in the
shoulder, elbows and wrist generating accuracy and speed. A lot of force also
can be generated from the stance of the basketball player at the time and their
alignment of their hips and shoulders as their chest passes are played in a
different context. This skill will always require a step forwards to exert
force onto the ball as the ball is heavier and it at some stages of the game
needs to cover a little more distance than what a chest pass does in netball.
Using all the research conducted on the biomechanical principals required for a
chest pass it could lead to improvements in all performance areas of a skill in
a game. It can also have a positive impact on the athlete as it could enhance
there learning of the skill resulting in a positive impact on their performance
of the skill. It also allows the athlete to apply and transfer these
biomechanical principals to other sports skills, as mentioned above.
Reference List:
Hatze, H. (1975). The meaning of the term
"biomechanics". Journal of biomechanics, Vol.7(2), pp.189-90
Blazevich. A. (2010) Sports Biomechanics. The basics.
Optimising human performance. Pp.196-205
Spiter,T..
Cochrane,J. Hart, N. Haff, G. & Nimphius, S.(2013)
Effect of strength on plant foot kinetics and kinematics during a change of
direction task Volume 13, Issue 6. pages
646-652
Talk Basketball. Basketball Passing. (2007) http://www.talkbasketball.co.uk/guides/basketball_skills_passing.html.
Street basketball blog.
Basketball shooting techniques, fundamentals and form. http://street-basketballss.blogspot.com.au/2012_09_01_archive.html.
(2012).
