مجلة الرافدين للعلوم الرياضية (Aug 2022)
A comparative study in the vertical work done and the ball launch angle between the Float and crushing services of jumping in volleyball
Abstract
The aim of the research is to find out - Recognizing the vertical work done and the angle of launching the ball for the skills of the smash and Float serve from jumping in volleyball. - Recognizing the differences in the vertical work done and the ball launch angle for the skills of the smash and Float serve from jumping in volleyball. The researchers hypothesized: - There are statistically significant differences in the vertical work done and the ball shooting angle between the skills of the smash and Float serve from jumping in volleyball. The researchers used the (descriptive) approach for its relevance to the nature of the research, and the research sample consisted of (6) players representing the Mosul University team for the year 2021 in volleyball, and the questionnaire, measurement, scientific observation, test and evaluation were used as means of data collection, where the research variables were determined through the analysis of similar studies and special literature With my smashing and Float serve skills from volleyball jump. Mass and length were measured, players were tested with three serves of each type (crushing and wavy), and the best serve of each type was evaluated for kinetic analysis. The scientific observation was carried out using a video camera placed next to the player with a distance of (4.35) meters and a lens height of (1.45 meters) and a scale drawing of one meter in length was used, images in the horizontal and vertical positions, to calculate the coefficient of change from the image to the truth to obtain the kinematic variables. The data was statistically processed using the SPSS program to obtain (arithmetic mean, standard deviation and t-test for related samples) and the equations that are related to the biomechanical variables. The researchers concluded: - The value of the completed vertical work was of a higher value when performing the skill of crushing serve because of the higher value of the vertical distance traveled to the center of mass of the body. - The value of the ball shooting angle was a higher value when performing the skill of Float serve. Through the conclusions, the researchers recommended: - The necessity of emphasizing on jumping high during the performance of the transmission skill to obtain the maximum height of the center of mass of the body and thus obtaining the appropriate amount of kinetic thrust. - Emphasis on training the rapid strength of the lower extremities for volleyball players because of its importance in achieving a higher jump and thus the height of the center of gravity of the body mass and achieving greater vertical work. - Paying attention during training to the Float serve from the jump, provided that the ball is not thrown at a great height and that the height is appropriate, which provides a good flight angle.
Keywords
