The relation of some kinematic variables to the server threw from the top in volleyball

Introduction

The process of reaching the highest levels and achieving victory over sports teams depends on many elements, including the training process that is witnessing continuous development in terms of skill development and training, diagnosing the requirements and mistakes that the player may make, in addition to studying the physical, physical, psychological and functional requirements that help raise the level of achievement. Volleyball is one of the team games that is characterized by its multiple skills and sequence, and the possession of its players’ physical abilities and body measurements, which are the cornerstone of the successful training process, as no matter how great the coach’s training abilities are, he cannot be considered a champion without them.

We find that the variables Kinematics has a definite and direct relationship to the best performance of the skill, and the more these measurements and variables are present and within the conditions for choosing a player, the better the player will be when performing the skill of serving, not just serving, but all the special skills of the game.

1.1. Research problem and Areas

Volleyball is considered a distinctive organized game that contains a set of motor skills subject to a special law that determines the methods of playing it and determines the number of team players.

Through the two researchers’ practice of the game during the study stages and through numerous field observations of the students’ and various teams’ training, it became clear to them that correct foundations had not been established for selecting male and female players according to some kinematic characteristics.

It would have a positive impact on the advancement of the player’s level and the teams’ achievement of advanced results if the two researchers noticed a weakness in the performance of the serve from the top in volleyball for the students of the fourth year of middle school, through surveying the opinions of experts, specialists, and teaching educators in schools. This is what sparked the interest of the two researchers to conduct this study to find out whether there is a contribution to physical abilities and some kinematic variables, and this is what leads the researcher to ask: kinematic variables and the performance of the serve skill from the top in volleyball.

Areas:

1. The human field: – A sample of fourth-year middle school students at Ur Mixed Secondary School for the year (2022-2023).
2. Spatial field: – The school yard (volleyball court) is open to Ur Mixed Secondary School, Al-Khalis District - Sindhi.
3. Temporal field: – For the period from 12/18/2023 until 1/20/2024.

1.2. Research methodology

The method “is the method by which a person, in a logical, scientific manner consistent with reality, arrives at an awareness of one of the facts that he was ignorant of, and it is the way to acquire certain knowledge” (Nuri Ibrahim Al-Shouk and Rafi’ Saleh Al-Kubaisi: 2004:51.). The descriptive approach relies “on studying reality or the phenomenon as it exists in reality and is concerned with describing it accurately and expressing it qualitatively and quantitatively.”) Ismael Khalil: 2010: 111), Therefore, the researcher used the descriptive approach using the case method and correlational relationships as it suits the research problem to know the extent of the relationship between two or more variables.

In other words, “the extent of agreement between variables in one factor with variables in another factor” (Wajih Mahjoub, 2001: 287).

1.3. The research community and its sample

Choosing a sample is one of the main steps in collecting data and information. The researcher often resorts to defining his research population based on the phenomenon or problem he chooses. was determined intentionally: fourth-grade middle school students aged 16-17 years. Ur Mixed Secondary School, Al-Khalis District, Diyala Governorate, for the academic year 20 23 – 20 24, with one section that was deliberately selected. Five students who did not belong to the stage in terms of age were excluded, and ten other students were subjected to the exploratory experiment.

The percentage of the sample was 62.5% of the original research community.

Table 1

Shows a description of the research sample

Search tools: It is the means or purpose through which the research objectives are achieved and accurate and correct results are obtained. It is divided into:

1. Methods of collecting data:

• Note.
• The questionnaire.
• Tests and standards.

2. Means of collecting information:

• Sources and references.
• Previous studies and research.
• The international network (the Internet).
• Scientific observation.

3. Methods of data analysis:

• Data collection and emptying form.
• Statistical methods.
• Computer laptop (DELL).
• Manual calculator.

4. Auxiliary means:

• Electronic watch.
• Legal volleyballs (5).
• Referee whistle.
• Colored adhesive tape to mark precision areas.
• Legal volleyball court.
• Wooden numbers numbered in English.
• Wooden rulers, length (1.5 m) and width (5 cm).
• CD disks.
• Assistant work team

1.4. Research procedures

1. Nomination Kinematic variables and physical measurements by experts.

In order to identify the most important kinematic variables for the research sample, researcher Tan prepared a questionnaire to survey the opinions of experts and specialists. Then he asked the experts to put a mark (*) in front of the appropriate test. After collecting and transcribing the data, the percentage for each test was calculated, adopting a percentage of (50%) or more, to determine the required tests as shown. In the following table 2:

Table 2

It shows the percentage of experts choosing kinematic variables

Note that the number of experts is (5) experts for each variable.

2. Volleyball skill tests:

After determining the skill tests for volleyball by experts and specialists, the selected tests will be presented and explained.

3. Testing the transmission skill:

Test:

• Transmission test Facing from above (Marwan Abdel Majeed Ibrahim: 2001: 293).
• The purpose of the test: – To measure the accuracy of serving skill.
• Tools used: a legal volleyball court, a goal marking tape, a measuring tape, and 10 volleyballs.
• Specifications: The tester performs the serve by directing the ball towards areas (A, B, C, D).
• Conditions: The laboratory has three attempts.

4. Points for each attempt inside Zone A.

5. Points for each attempt inside zone B.

6. One point for each attempt inside area (C).

7. One point for each attempt inside zone D.

Zero. When the ball falls outside these areas.

• When the ball falls on a common line between two areas, the score of the higher area is calculated.
• The attempt will be canceled if the laboratory commits a legal error. The highest score for the test is (12), while the highest score for the test is (0).

Fig. Demonstrates the accuracy test of the skill of the serve facing from above in volleyball

1.5. Exploratory experiments

The exploratory experiment is one of the basic conditions in scientific research, as through it the researcher can learn about many things related to the mechanism of implementing the research. It deals with topics for which there is no information or data or the researcher is ignorant of many of its aspects and dimensions. It is “a small experiment or work.” A summary of the existing study carried out by the researcher in order to identify the negatives that may accompany conducting the main research experiment (Nuri Ibrahim Al-Shawk and Rafi Saleh Fathi: 2004: 89). The exploratory experiment aims to:

1. Identify the responsiveness of the sample and apply the test.
2. Training and arranging the assistant work team.
3. Ensure the safety of the devices used in research and their suitability to complete the tests.
4. Identify the time taken to implement tests.
5. Knowing how to obtain data and how to collect it in order to be processed statistically.
6. Finding scientific coefficients for tests.

Researcher Tan conducted the exploratory experiment to test the transmission skill on Wednesday 12/20/20 23 at ten in the morning on the playground of the school courtyard of Ur Mixed Secondary School for the fourth stage of middle school.

There were (10) students who were also excluded from the main experiment of the research. The aim of conducting the exploratory experiment was to identify the obstacles that the two researchers may face during the implementation of the experiment. The main thing is to know the extent of the students’ understanding of the vocabulary of the tests under study, and to ensure the suitability of the devices used and the dimensions of the cameras. Knowing the time it takes to conduct the tests and knowing the efficiency of the assistant work team.

Statistical Package for Social Sciences (SPSS) was used to process the results obtained by the researcher to extract the results using the following statistical methods:

1. Arithmetic mean.
2. Deviation.
3. Mediator.
4. Coefficient.
5. Correlation coefficient.

1.6. Results

Show results the correlation coefficient and its error rate between the transmission skill, and the most important results obtained by the two researchers are as shown in table 3:

Table 3

Descriptive variables for the research variables

Descriptive variables for the research variables are as follow shows the values of the arithmetic mean, standard deviation, and skewness coefficient for the research variables. The values of the averages are greater than the standard deviations and indicate the absence of dispersion among the members of the research sample, as the values of the skewness coefficient ranged between (0.01 – 0.73), meaning that it was limited to (± 1) Which indicates that it is within the moderate trend.

Presentation and discussion of the results of the correlation between kinematic variables and serving skill.

Table 4

It shows the correlation coefficients between physical measurements, kinematic variables, and serving skill

The value of the tabular T was (2.31) at 8 degrees of freedom and a significance level of 0.05.

It is clear from the table that there is a statistically significant correlation between the kinematic variables and the skill of serving, as the correlation coefficient between the launch angle test, which represents the skill of serving from the top was 0.91, and the elbow angle, the skill of serving from above, was 0.87, which reflects its importance in performing the serving skill.

The skill of serving from the top requires the use of a high level of explosive power of the arms to push the ball, enabling the student to hit the ball. This was confirmed by Sawsan Jadoua, “The importance of the explosive power of the arms for the skill of serving from the top comes from the technique of the skill that directly requires the explosive power of the muscles of the arms to perform a hit.” & Quot; Powerful and influential & quot; (Sawsan Jadoua: 105:2001). The role of the speed of the ball’s launch in the skill of serving from above is highlighted by hitting the ball strongly and quickly, and this is what was confirmed by (Faten). Ismael Victorious, 2000: 35-36. “A student who lacks arm strength cannot receive a strong serve.

The student who has explosive power and a high speed of launching the ball helps him to rise to a high level, which makes him perform the skill of serving from above successfully. This student is considered a source of danger to the opposing team, despite the importance of kinematic variables. to another in performing the skill of the serve skill from the top, but it had weak correlations with the performance of the skill of the serve skill from the top. The researcher attributes the reason to neglecting training in some kinematic variables at the expense of other physical abilities, which made the sample members distinguished by one ability over another.

Added to this is the lack of interest in selection, which is One of the important things in preparing a volleyball player, especially a student striker.

Researcher Tan believes that serving is an important offensive skill, especially if the serve is executed accurately.

Through it, the student can gain direct points for the team, in addition to the psychological impact that it can have on the opposing team, and that the higher the student’s physical ability, the better the performance, not only with the skill of serving, but with all skills. Activities, when there is no physical ability in terms of motor abilities, such as motor speed or explosive force, in addition to endurance, leads to the inability to perform the skill and thus affects his level. Serving is considered one of the most prominent skills in volleyball and one of the most difficult skills because through it, a point is earned for the team. “If the serve is perfected, the team achieves a great momentum towards victory in the first moments of the match, especially if the serving student is able to determine and direct the serve.” (Marwan Abdel Majeed: 2001: 52). The serving skill is one of the offensive skills that requires the student to be intelligent in directing the serve to good places to score points.

There is also a correlation between the speed of launching the ball and the skill, as the faster the ball is, the better it is in performance. The accuracy of the serve. As for the rest of the kinematic variables, there is no relationship or percentage of contribution. This is because the skill of serving is a skill far removed from contact with a teammate or competitor, that is. The player 39; s free movement may have an effect, but it is not clear as it is with skills the other.

Conclusion

The researcher conducted the main experiment to test the transmission and photography skills of motor analysis was conducted on Thursday, January 11, 2024. On the samples and in the presence of the assistant work team.

There is a significant correlation between some kinematic variables and the performance of the volleyball serving skill. Recommendations to emphasizing the importance of kinematic variables that have shown significant relationships in transmission performance, working to develop them and taking this into account in developing training programs and plans.