On The Agility Theory Of Elite Beach Volleyball Players In China And Its Influential Factors

Agility is one of the most important physical qualities in sports, especially for the players who play with a ball. Agility is the key of their technology to some extent. According to the studies of agility from both internal and external experts, the paper studies the agility, and more than ninety excellent beach volleyball players in China had been selected for testing. By means of documentary, questionnaire, testing and statistics methods, the study discussed the definition, classification, structure, characters, influencing factors, training principles of agility as a starting point. The article made a systematical expatiation on the basic theory of agility, and the article also made a preliminary study into the influencing factors’structural equation modeling of agility, taking the Chinese beach volleyball players as an example. This paper came to the following main conclusions:1. According to the methods and principle of definition in logic, we defined sport agility as following, in the sports scene, the people experience stimulus and respond to the suimulus by changing direction and/or body movement to adapt the circumstance as needed.According to the methods and principle of classification in logic, we divided agility intl the following three categories, anticipate and decision making ability,changing direction ability and changing body movement ability.Characters of Agility, quickness and changing were the essential characteristics of agility, and agility also had the following basic features, distinct project features, staggered growth features, highly heritable and changeable features, accurate and standard technique features.2. Anticipate and decision making ability of Chinese beach volleyball player was related to speed perception. Changing direction ability was influenced by distance of single leg jump (both the right and left), height of run-up vertical jumping, strength of both abdominal and dorsal, length of trunk bending forward, braking and starting ability, time of30m run, height and weight of body. Changing body movement ability was influenced by single leg jump (both the right and left), height of run-up vertical jumping, strength of both abdominal, braking and starting ability and time of30m run.3. The liner regression equation of changing direction ability which has been verified by the excellent beach volleyball players in China is Y=5.716-0.999X distance of the left foot jump+0.316X strength of dorsal+0.952c×time of30m run, which can explain59.9%common variance of changing direction ability. The liner regression equation of changing movement ability which has been verified by the excellent beach volleyball players in China is Y=5.506+0.567X time of30m run+1.066Xstarting ability, which can only explain19.2%the common variance of changing movement ability.4. By using the method of percentiles or progressive scoring the paper provides the evaluation criterions of anticipate and decision making ability, changing direction ability and changing body action ability respectively for the beach volleyball players in China. The study also gives the comprehensive estimation for agility as following: Y=0.413×score of anticipate and decision making ability+0.306×score of changing direction ability+0.281X score of changing movement ability.