Biomechanics Blog: Badminton Overhead Clear

Skill Acquisition and Biomechanics for Physical Educators

HLPE 3531

Danica Klemse 2121419

Image Reference: http://www.freewebs.com/badmintonlonneke/fordrop.gif

Introduction:
When executing the skill of a badminton overhead clear, a number of biomechanical principles influence the result of the shot, whether it be successful or not. Badminton overhead clears are the most commonly used during a game. They are used to move the opponent to the back of the court, and create space in the front section (Manrique & Gonzalez-Badillo, 2003). If we are trying to understand how badminton technique can be optimized to increase maximum technique, we must understand the different sorts of shots that impact the results.  In badminton there are two types of clears; attacking and defensive clear. An attacking clear has a trajectory that runs almost parallel to the ground (Manrique & Gonzalez-Badillo, 2003). The shuttle travels flat and fast towards the opponent, as seen in the image below. The attacking shot allows less time for the opponent to get behind the shuttle, causing weaker returns.

Image Reference: http://www.badminton-information.com/badminton_clears.html

A defensive overhead clear has a high and deep trajectory, as seen below. These badminton shots allow more time for the player to return to base position and prepare for the next shot (Manrique & Gonzalez-Badillo, 2003).

Image Reference: http://www.badminton-information.com/badminton_clears.html

 
Breakdown of the overhead clear:1. To execute the shot turn sideways with the non racket foot forward.
2. Prepare the racket by lining the racket head and the non racket hand up, pointing towards the shuttle.
3. Follow the line of the shuttle back with the racket and hand, until just before the shuttle is in hitting range.
4. Draw the racket back behind the shoulder and form a throwing position.
5. Reach up and attack the shuttle as early as it can be hit, ideally directly above or slightly in front of the hitting shoulder.
6. At this point, the body should turn in, transferring body weight forward, bringing the racket hip then shoulder through.
7. The follow through should leave the dominant side slightly closer to the net when the shot is executed.
(Tsai, Huang, Lin & Chang, 2000).

 

Major Question:
Using biomechanical principles, what constitutes of optimal, efficient technique in an overhead clear?

Answer
Summation of forces:
In badminton, energy is transferred from one movement to the next. Summation of forces involves the individual forces that produce successive movements being added to create a larger total force. There is no break in the transfer from one movement to another; each movement should begin at the moment the last force has reached its maximum potential (Blazevich, 2010). Below, shows examples of correct and incorrect timing of summation of forces;

The correct sequence for summation of forces is the heavier, stronger parts move first, followed by the smaller and faster body parts (Perreault, Day, Hulliger, Heckman & Sandercock, 2003). An example of this is when kicking a football into the goals.  The force starts in the leg when the leg is brought back. It then travels to the hip and knee when bringing the leg forward to kick. It finishes off with flexion of the foot when kicking the ball. By the larger body parts moving first and the smaller ones following through, this allows the maximum force to be created and transferred into kicking the ball. This concept of summation of forces can be directly applied to the movements in a badminton overhead clear. Below, shows an example and movement break down of what a badminton overhead clear should look like;

Video Reference: https://www.youtube.com/watch?v=qhe_rRJR9_Y

This is a good example of summation of forces. This is because the player has their feet apart , which creates a good support base and lower centre of gravity (as seen below). It can be seen from the video and image below that the player is leaning onto their back leg, ready for weight to be transferred to the front leg. The player’s body is side on and moves their hips and legs first to generate more force. It can be seen that the player is stepping forward during skill execution, this is important to step in the direction of the force  to heighten force summation. This shows that they uses the bigger body parts first (legs and hips) and then the force moves through to the smaller body parts (arm and wrist). The rotation of the shoulders and hips means they are able to generate enough momentum force to produce a quick movement.

 Image Reference: https://www.youtube.com/watch?v=qhe_rRJR9_Y

Centre of Gravity:
Centre of gravity is 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 (Blazevich, 2010). The force of gravity only applies a force downwards towards the earth but we could look at the body from any direction. Centre of mass and centre of gravity are basically the same, except that centre of gravity is only used to indicate the centre of the body in the vertical direction (Blazevich, 2010). It is important to understand the influence of centre of gravity when it comes to playing badminton. Centre of gravity is behind the stability of the shuttlecock during flight (Cooke, 1996). To achieve this principle, lower centre of gravity involves; crouching legs stance, with legs apart to widen the base of support, as shown in the picture below. Having a good structure is very important, as it allows more control of the shots and a strong base allows the player to get into position.

Image Reference: https://www.youtube.com/watch?v=qhe_rRJR9_Y

Angle of release/ Projectile Motion:
As soon as an object is thrown it becomes a projectile (Blazevich, 2010). Once an object is released it follows a predetermined parabolic path. Once the projectile is released, the predetermined path can be influenced by air resistance and gravity. Before the projectile is released it can be influenced by the speed, height, and angle of release (Blazevich, 2010). As seen in the image below, an object that is released and landing at the same level has the optimum angle of release of 45 degrees to achieve the maximum distance. In sport, the angle of release in a projectile motion can affect the distance achieved, which is shown in the diagram below. The larger the height of release, the smaller the horizontal distance covered.

Image Reference: http://www.scienceworld.ca/sites/default/files/PopBottleRocketPartII_2.png

Image Reference: https://www.youtube.com/watch?v=qhe_rRJR9_Y

This picture above, shows the optimum angle of release in an overhead clear. The shot has a higher chance of following the predetermined parabolic path as it follows a angular motion once released. The ideal angle of release for an overhead clear is much smaller than the angle of release for other badminton shots (smash). As it makes contact with the badminton racket, it follows an angular motion and if released correctly, at the right angle, it should reach the back of the court (Yap, 2010).

 

Leverage:

A leaver is a mechanical device that makes work possible and easier in most cases, for example; someone holding a bat or racquet which would increase the length of the lever. As seen in the diagram below, a lever consists of three basic components:
1. Effort: A degree of effort must be applied to ensure movement
2. Load: The resistance that the effort attempts to overcome
3. Fulcrum: The centre of rotation or the axis around which the effort and load arm rotate
(Hamill & Knutzen, 2006).

Image Reference: http://www.toddherman.com/images/eupdate/2008/200809_lever1.gif

A lever that is longer has to travel the same distance in the same amount of time (Keele, 1968). An experiment was conducted and the image below demonstrates the results, the balls are hit at the same time but the outside ball will travel further than the inside ball. This is because the longer lever has travelled a further distance in the same amount of time, therefore the level travels at a faster velocity. As more velocity is generated behind the outside ball this will result in more force, and travelling further.

 

The picture below, shows an example of optimum technique when hitting a shot. By having a straight arm this creates a longer lever. This means more velocity is generate within the shot, therefore more force is able to be applied, resulting in the shuttle travelling a further distance. Also, by having a straight arm the player is able to control the shot and direct the shot where they plan. In badminton, it is also vital how the racquet is held. As the image shows, the racquet is being held at the lowest point, which again increases the lever length.

 Image Reference: https://www.youtube.com/watch?v=qhe_rRJR9_Y

How can we use this information?
We can use the principles explored above to analyse and experiment with different techniques to develop the skill and make it more efficient. As the badminton serve is so biomechanically detailed, this blog would be helpful for many sport professionals and coaches, as the biomechanical principles can be applied to a variety of sports, especially racket sports. For example; the summation of forces can be applied to sports like golf swing, volleyball and tennis serve or batting and bowling in cricket. Many sports also involve using centre of gravity and a wide base of support. Sports such as; golf, hockey, cricket and squash involve the use of lever length and grip, to achieve maximum ball velocity to increase performance. The angle or release/ projectile motion can be applied to any sport that uses a ball or any other equipment that is released into the air, in aim to travel distance. For sports that involve equipment, it is important that the sports person is aware and using the equipment at the optimum potential. This will increase the overall performance of the skill execution. By having basic biomechanical principles related to the sport, this will allow them to learn and practice the best way of executing the skill to increase optimum performance.

References:
Blazevich, Anthony (2010). Sports biomechanics: the basics : optimising human performance (2nd ed). A. & C. Black, London

Bojanglesbadminton. (2008, November 11^th). Badminton Technique- Forehand Clear [video file]. Retrieved from: https://www.youtube.com/watch?v=qhe_rRJR9_Y

Cooke, A. J. (1996). Shuttlecock design and development. The Engineering of Sport, 91-95.

Hamill, J., & Knutzen, K. M. (2006). Biomechanical basis of human movement. Lippincott Williams & Wilkins.

Keele, S. W. (1968). Movement control in skilled motor performance. Psychological bulletin, 70(6p1), 387.

Manrique, D. C., & Gonzalez-Badillo, J. J. (2003). Analysis of the characteristics of competitive badminton. British journal of sports medicine, 37(1), 62-66.

Perreault, E. J., Day, S. J., Hulliger, M., Heckman, C. J., & Sandercock, T. G. (2003). Summation of forces from multiple motor units in the cat soleus muscle. Journal of neurophysiology, 89(2), 738-744.

Tsai, C. L., Huang, C., Lin, D. C., & Chang, S. S. (2000). Biomechanical analysis of the upper extremity in three different badminton overhead strokes. In ISBS-Conference Proceedings Archive (Vol. 1, No. 1).

Yap, C 2010, Badminton Clears, Badminton Information, accessed 18 June 2015, <http://www.badminton-information.com/badminton_clears.html>.