What are the biomechanical principles which help the performance of the netball player improve the accuracy of her goals?

HLPE3531 – Assignment:  Biomechanics Blog

Ellie Baldwin 

Biomechanics of a Netball Shot

What are the biomechanical principles which help the performance
of the netball player improve the accuracy of her goals?

Introduction of Biomechanics and the importance of shooting a goal in netball

Netball is the most popular women’s sport in Australia with an estimated amount of one million players nationwide.  The game is a ball sport played by two teams of 7 players, who must work together within their specific positions to score a goal up their end (Netball Australia, 2014).  The game requires skilful play, strategic thinking, agility and endurance and heavily requires on teamwork and achievements from individuals in their own positions (Australian Government , 2014).  Biomechanics aspects also feature as a key role in playing a successful game of netball.  McGinnis (1594) explains that biomechanics is a study of forces and their effects on living systems.  The following discussion will explain the understanding of the biomechanical principles which help in a game of netball and benefit a goal shooter to have more successful attempts at goals.

What are the biomechanics of a netball shot?

To create a successful netball shot there are a few movements which need to be performed correctly for the best outcome.  These include;

·         Shooting action

·         Balance and stability

·         Ball release and distance shooting

Shooting Action:

Forces are defined as a push or pull action, or anything that causes or has potential to cause movement (Steele, 1990).  The force directed upon the ball as it travels to the goal ring is often referred to as Newtons Law of Inertia.  This law states:  The acceleration of an object is proportional to the net force acting on it and inversely proportional to the mass of the object (Blazevich, 2010).

Figure 1 shows the four common properties of force;

Magnitude – the amount of force and how much is applied

Direction – the angle at which the force is applied

Point of application – specific point or area where force is applied

Line of action – demonstrates the point of application in which the force is acting

A goal shooter in netball uses all parts of their body to help shoot the ball.  Players demonstrate greater flexion of the knees and shooting elbows which allows more adequate force helping to propel the ball to the goal ring (Steele, 1990).  Sufficient hyper-extension of the hand to stabilise the ball may also take place with minimal movement of the trunk, arm and forearm movements during the shooting release.  This allows greater release height and greater release velocity (Steele, 1990).

Figure 2 shows flexion of the players’ elbows, ready to shot the ball.

Balance and stability:

Blazevich (2010) explains “the point around which all the particles of the body are evenly distributed, and therefore the point at which we could place a single weight vector is the body’s centre of gravity.”  A body’s centre of gravity can shift and change, depending on the actions being performed.  This is why it is important (as stated above) to have minimal movement of the upper body, including trunk and arms, which will enable more chances to execute accurately.  It is important in lots of sports that the players’ are able to main balance and stability, loss of this can have effects on their overall performance of the skills needed in the sport played (Hede, Russell & Weatherby, 2011).

Ball release & Distance Shooting:

The release point of the ball is directly above the players head. Upon this happening the trunk of the body is straight and the head is upright facing the goal; in some cases shooting players will extend their arms more to help with the release.  The release height and angle is all influenced by extension of the knees, arms and elbows (Steele, 1990).  When the shooting distance has increased, shooters will require a change in their shooting action, involving; an increase in force, increased speed of motion and deeper flexion of arms, knees and elbows to gain greater force.

Does the push-like or throw-like movement pattern provide a more beneficial outcome in a netball goal shot?

The push-like movement is when the joints move at the same time, while the throw-like movement is when one movement is completed to form another movement to help transfer the weight.  The common movement phase used when throwing the netball into goal is the push-like movement.  This action represents the pushing of the ball off the hands allowing all joints to extend in conjunction with each other (Blazevich, 2010).  Using the push-like movement provides optimal opportunity to score as the kinetic chain forms a straight line which follows each sequence movement.  Allow the line to followed helps to increase the accuracy of the goal as all are pointed in the same direction.

The process for releasing the ball into the ring using the push-like movement can be thought of as; firstly providing a stable base for support (through the arms), slight bend in the knees and arms, then an upward motion using the knees and extension of arms to push the ball forward and pushing the ball off the tips of the fingers in an upwards direction heading for the goal ring.  This type of movement uses all areas of the body and allows optimal opportunity for force and accuracy (Blazevich, 2010).

How can force be applied with the optimal result and how can this be furthered applied?

Blazevich (2010) says that optimal force is “the product of mass and acceleration; includes a change in the mobile state of an object.” While the ball is in place in the players’ hands it is in the state of rest and the player’s position is that of static balance.  Force must be applied in order to change the inertia of the ball.  Using Newton’s second Law it is said that the greater mass of netball is needed, for more force to be acted on.  Depending on how much force is needed to allow the ball to make the distance its needs to travel says how much force is required to score a goal.  The push-like movement action will help the force be applied to the ball, helping it to make the distance.  Evidence of this would show in the comparison of where to people were standing in the goal circle to shoot the ball; someone standing directly under the ring would use less force and flexion of knees and arms, while someone standing on the edge of the goal circle, will direct all of their force and energy towards the ring.

While many rules and skills are transferable between sports, netball is limited due to the rules set in the game.  Although no movement can be made once the ball is in the possession of the attacking team, players need to think quickly about the context in which they are in to help them perform to a high quality (Blazevich, 2010).  It is important that the person shooting the ball remembers the importance of the positioning of their body and their balance to help them gain enough force in pushing the ball towards the ring.

Through further investigation it could be seen that projecting the ball up into the goal ring, using backspin can further improve accuracy of the overall shot.  Using this type of throw can help maintain flight direction and decrease the ball speed on impact with the goal ring.  This may then offer a better chance for the ball to rebound off the ring and through for a scored goal.

Analysing the biomechanics of any sport can be a vital part in the way a game is played as it allows coaches and/or teachers to instruct players and students to execute the skill to their optimum outcomes. Once a player understands the forms and styles of the game and can put these into practice, the quality of the game can be greatly increased.  It is ideal for junior players to be taught the theoretical background of a skill, as this will allow for they to achieve optimal technical performance during a game (Steele, 1983).

It is important in this documentation to realise that the shooting position is an important part of the netball game, analysing this stage of the play can help provide coaches to understand the basics to teach netball fundamental movements to players of all experience levels, which will help to achieve optimal technique performance and moving in correct ways to minimise potential injury (Steele, 1990).  It is important to learn the steps to help progress the game further, acknowledging the biomechanics behind each and every movement.  There will be other sports in which this information can be adapted to use and will help students to think more critically about sports and how to improve their performance.

References:

Australian Government.  (17 June 2014).  Netball – Australian Institute of Sport.  Retrieved from Australian Sports Commission: http://www.ausport.gov.au/site_tools/site_search?query=netball&collection=ASC&form=simpleFragment

Blazevich, A. (2010)  Sport biomechanics the basics: Optimising human performance.  London, Bloomsbury:  Black Publishing.

Hede, C., Russel, K., & Weatherby, R., (2011)  Applying biomechanics to sport (3 ed.) New York: University of Oxford.

Investigator College (17 May 2012).  Shooting for Gold.  Retrieved from:  http://www.investigator.sa.edu.au/shooting-for-gold/   (Figure 2)

McGinnis, P.M., (1954)  Biomechanics of Sport and Exercise (2 ed.)  Champaign, IL: Human Kinetics.

Netball Australia (17 June 2014).  What is Netball?  Retrieved from Netball Australia:  http://netball.com.au/our-game/what-is-netball/

Seelander, K. (29 April 2013).  Biomechanics of  a Netball Shot.  Retrieved from:  http://kimberleyjs.blogspot.com.au/  (Figure 1)

Steele, J. (10 August 1990).  Biomechanical factors affecting performance in netball. Implications for improving performance and injury reduction.  Retrieved from PubMed.gov:  http://www.ncbi.nlm.nih.gov/pubmed/2204101