Technique Analysis PDF

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BIOMECHANICS – TECHNIQUE ANALYSIS Identify and separate the skill (volleyball spike) into key subroutines. (Preparation): 1. Build momentum through running to desired position. 2. Begin to leap towards target with your preferred foot in the direction of the ball using energy converted from forward to vertical. 3. Accelerate by jumping up (towards target- being the ball) and swing your arms back with palms facing up. (Jump): 4. Swing arms up simultaneously whilst jumping for an increased vertical height gain. Force summation via the transfer horizontal momentum into vertical momentum.

(Arm Swing): 5. At this stage, the desired hitting arm should be ready in position to hit the ball whilst the opposite arm is reaching high directing the ball in the preferred direction. Rotation of body at 90 degrees to target, hitting arm behind head. (Hit): 6. The use of core muscles and shoulder rotation is used to transfer power through to the hit. 7. Finally, swing arm through the ball using gained momentum- see Figure 1. Sequence- force summation - Rotation of hips and shoulders, extension of arm creating long lever, flexion of wrist

Figure 1: key subroutines of a volleyball spike [ CITATION Gra15 \l 3081 ] (Follow Through) 8. After hitting the ball, the hitting arm follows through by going across the body to prevent the deceleration of the arm. This is seen to produce more power and therefore results in the projectile having as much force applied as possible. This is then stabilised through a steady and stable two-foot landing.

Identify and explain the 4 most important biomechanical principles that apply to this skill and how they impact the outcome of performance. The Magnus Effect and Air Resistance The airborne time of the volleyball can be reduced by an athlete placing topspin on the volleyball. This causes the ball to fly in an aerodynamic potency of the Magnus effect [ CITATION Amy14 \l 3081 ]. This inevitably pushes the ball downward in order for it to land faster- see Figure 2 [ CITATION Amy14 \l 3081 ]. Additionally, this also reduces the time the opposing team has in regards to determining a way in order to return the ball.

Figure 2: The Magnus effect is a spinning object that drags air faster around one side, creating a difference in pressure that moves it in the direction of the lower-pressure side [ CITATION Amy14 \l 3081 ].

Velocity of Release In Volleyball, the velocity of release is the most influential factor when spiking in order to maximise the horizontal distance the ball will travel and the speed the ball will hit the ground. Athletes need to take into consideration the fact how the greater amount of force applied, the greater the velocity at release will be- see Figure 3. Therefore, the further the projectile can travel. If the athlete applies too much force onto the volleyball, it is more likely to land out of play and therefore, they can potentially lose vital points through an issue that can be easily rectified. Additionally, the amount of force that the athlete applies to the volleyball has a vital influence on how quickly it can hit the ground; therefore earning a point.

Figure 3: velocity of release exemplifying variations.

Levers Another crucial principle that is often applied to the skill of a volleyball spike regards the biomechanical aspect of levers. This has a major impact on the outcome of the performance for athletes as the skills needed are crucial to complete a volleyball spike- therefore; one bad sub routine has the power to ruin the entire effectiveness of the skill. It can be noted how important it is for the volleyball spiker to contact the ball with the hitting arm being at full extension. This is to assist with maximising ultimate power and control. As the spiker makes contact with the ball, they should be stopping the proximal segments which eventually results in a high velocity of the end point (being the hand)- see Figure 4 [ CITATION Ant16 \l 3081 ]. In volleyball, (whilst spiking) the arm becomes a third class lever whereby the goal is to maximise momentum and therefore, speed [ CITATION Ant16 \l 3081 ]. When the human body creates a third class lever, the muscles throughout the body only move for a short distance. However, the arm which acts as the end of the lever moves a much greater distance. This creates a fast movement at the end of the lever and the speed that is generated will allow the athlete to spike the ball with sufficient speed. The shorter level during rotation (bent arm) making it quicker and easier to rotate. Arm extended on connection to increase velocity/ force.

Figure 4: Third class lever of the spiker's arm. It can be seen that the load is the inertia that the arm must overcome [ CITATION Ant16 \l 3081 ] Summation of forces: Simultaneous on take-off and sequential in the hit Force summation regards an athlete’s ability to obtain maximum force through the use of many muscles in sequence- see Figure 5. This is seen through the larger and stronger muscle groups. Additionally, the smaller muscles are used in fine movements and co-ordination. Movements are initiated by the larger, stronger muscles and progresses through to the smaller muscle groups. The use of as many body parts as possible is desired in order to increase the force produced. The timing of these movements are important for the transfer of momentum from one muscle group to the next. A stable base for each movement is required so that this momentum transfer can be maintained. A volleyball player needs a good, stable base to initiate the movement to begin the spike. The timing of movements at each joint determines the control of the hand and the size and direction of the force applied to the ball. This results in a more powerful force that can be transferred to the ball so that it travels with momentum over the net to the opposite side [ CITATION Tim15 \l 3081 ]. Lastly, a stable base is required in order to conclude the sequential movement in a safe and constant manner.

Figure 5: sequential force summation [ CITATION Tim15 \l 3081 ] Identify a specific spike and using your knowledge of biomechanical principles, review the technique suggesting what needs to be corrected to improve the outcome of the performance. Image:

Review:

As seen, player 24 is seen to be receiving an attack from the opposing team.

Correction needed to improve the outcome of performance: -

Positioning on court.

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Team communication.

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Timing of movement.

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Body positioning.

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Gaining more momentum through utilising a leading vertical and horizontal jump.

It can be seen that the player is in the incorrect position as a starting setter. Player 24 is seen to be preparing for a spike. Her arm position is seen to be appropriate for the desired action. However, in the video, she is not seen to be taking the correct measures leading up to the play; this is usually a leap forward with the predominant foot. If there was no runup, no momentum would be produced therefore resulting in less vertical momentumcausing a lower height of release. Additionally, in the clip, it can be seen that the timing of the attack was

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mistimed as she is fixed too early. Therefore, this results in lacking the desired amount of momentum through not being able to utilise the power from the required leading jump. -

In the arm swing (hit), it can be seen that the athlete has a low angle of release.

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The momentum of play leading up to the hit has a vital influence on the projectile’s flight/ motion.

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In the clip, it is seen that the athlete is not successful in getting enough power behind the ball in order for it to get over the net.

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In the follow through, it can be seen that player 42 is not successful from the previous attempt at attack and therefore gains position back on court

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Angle release.

of

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Momentum.

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Gaining correct position back onto court.

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Reading the playknowing where the opponents next hit will be regarding the previous point played.

ready to receive the opposing teams serve. -

On the ground when contact is made, an increased angle of release is created therefore resulting in an increased ball flight.

BIBLIOGRAPHY: Dempsey, S. (2016). What biomechanics principles are involved in the volleyball spike and what is most crucial to optimize the spike? Retrieved from Biomechanics Blog: https://samdempsey123.wordpress.com/2014/06/19/what-biomechanics-principles-are-involved-in-thevolleyball-spike-and-what-is-most-crucial-to-optimize-the-spike/ Feher, T. (2015). Studies Revision Seminars. Retrieved from Stage 2 Biomechanics: http://www.pestudiesrevisionseminars.com.au/pdf/Stage_2_Biomechanics_2nd_ed_sample_package.pdf Haydrey, M. (2014). Biomechanical Principles. Retrieved from Science in Coaching: https://www.nzequestrian.org.nz/wp-content/uploads/Biomechanical-Principles-Resource.pdf Haydrey, M. (2014). Science in Coaching. Retrieved from Biomechanical Principles. Hughes, A. (2014 ). Biomechanical Principles of a Volleyball Spike. Retrieved from Blogspot: http://amyhughes027.blogspot.com/ McGrathe, G. (2015). How to learn Volleyball Spike? Retrieved from Volleyball Advisors : http://www.volleyballadvisors.com/volleyball-spike.html Skoumbros, A. (2016). What are the biomechanics underpinning a powerful and fast volleyball spike? Retrieved from Biomechanics Blog: The Volleyball Spike: http://antheasbiomechanicsblog.blogspot.com/ STA. (2011). Stability Principles and Balance in Sport. Retrieved from Sports Training Adviser: https://www.sportstraining-adviser.com/stabilityprinciples.html Vidmar, D. (2014). The Physics Of Volleyball. Retrieved from Real World Physics Problems: https://www.real-worldphysics-problems.com/physics-of-volleyball.html...