Kinematic Analysis On The Technique Of Blocking In Movement Of Assistant-attackers In Jiangsu Province Women's Volleyball Team

This paper analysis the key points of movement ,taking-off and blocking of blocking in movement of assistant-attackers in Jiangsu province women's volleyball team, using literature review, experiment research and statistics, etc. The analysis is very significant for improving and perfecting the technique of blocking in movement.The main research subjects of this paper is Lu Yan,Sun Hui and Li Kejia,who are assistant-attackers in Jiangsu province woman's volleyball team.The athletes'blocking technique when they move to 2,4-number member is shot with two Panasonic high speed cameras ,the frequency is 50f/s,and the photographs are analysis with the SIMI-motion Video Analysis Performance System.The research results demonstrate (1) at the first stage of blocking in movement ,Lu Yan's standing position is near 4-number member , Sun Hui's is near 2-number member, Li Kejia's is in the middle basically.Lu Yan moves from 3-number member to 2-number member by the footwork 2,moves from 3-number member to 4-number member by the footwork 1, she has great advantage on moving distance and time by adopting the two footworks,the practice effct is good;(2) Li Kejia's strength of lower limbs and speed are relatively good, the strength of upper limbs,waist and abdomen are relatively poor , so she has advantage while blocking , but her strength of upper limb, waist and abdomen are relatively poor,and her hanging time is short,as a direct result, the blocking effect is not nice; Lu Yan's strength of upper limbs, lower limbs , waist and abdomen are in balance, and her hanging time is longer. (3) when the buffering is highest in the stage of take-off buffering, The subjects bend knees too much ,as a result,the level speed loss increases ,and affects directly the speed, height of the subjects'taking off .While taking-off the subjects'stretching range of the hip , knee and ankle is not enough compaering with excellent athletes. While blocking in movement the subjects'average vertical accelerating stretching rang and average vertical speed of gravity at the left-off moment are bigger when the subjects are moving from 3-number member to 2-number member than moving from 3-number member to 4-number member,,it illustrates that while the subjects blocking in movement from 3-number member to 2-number member,they use the techniques better,and the hip , knee and ankle stretch fully.So the subjects'technique could be improved substantially in the blocking in movement from 3-number member to 4-number member.