躲避球冠軍選手不同投擲動作之運動學分析

Abstract

研究目的：以運動學分析躲避球選手在原地站立與移動步時，採用過肩與側肩投擲之差異。方法：以十名102年全國躲避球賽冠軍選手為研究對象，平均年齡11.86±0.54歲，平均身高158±9.16公分，平均體重52.34±17.33公斤。以十台VICON攝影機，及一台FASTEC高速攝影機，同步蒐集資料。以VISUAL 3D動作分析系統，計算人體運動學參數；球速部分以Kwon 3D軟體來計算。以SPSS20.0版統計軟體，進行無母數弗里曼二因子等級變異數分析，比較投擲動作之差異，顯著水準為α=.05。結果如下： 一、過肩動作：加速期至球離手時顯示有較大軀幹側彎角度、最大軀幹前傾角速度、肩外展角度，在球離手時有較大前腳膝關節角速度與肩軸角度較面向非慣用手方向。 二、側肩動作：加速期時最大軀幹旋轉角速度較大、球離手時有較大的重心合速度、向上分速度、肩軸角度較面向投球前方。 三、移動過肩動作：加速期至球離手時顯示有較大軀幹側彎角度、最大軀幹前傾角速度、肩外展角度，球離手時有較大前腳膝關節角速度與肩軸角度較面向非慣用手方向。 四、移動側肩動作：準備期有較長的跨步長百分比；加速期有較大的重心總位移、向前方向位移、軀幹旋轉角速度；球離手時有較大重心向上分速度、肩內旋角速度。 建議：就運動表現而言，移動側肩有較快球速、移動步有較長的時間控制；就傷害風險而言，過肩投擲軀幹側彎、肩外展角度較大，對肘外翻壓力帶來負面影響。

The aim of study is to analyze the diference between overarm throw and sidearm throw when the kinematics dodgeball players stand still and step in motion. Method: Ten national champion Dodgeball game players in Taiwan were served as the participants of the study. Their average age are11.86±0.54 years. Their average height is 158±9.16 cm; Their average weight is 52.34±17.33 kilograms. Also, ten Vicon Motion Capture systems and one Fastec High Speed Camera are used to be synchronized the data collected in the survey. The VISUAL 3D motion analysis system are utilized to show Kinematics calculation parameters. Calculation of Ball Velocity will be demonstrated by using Kwon 3D software. The variables of the Friedman two-way analysis of variance nonparametric statistical test was calculated by using SPSS 20.0 software to compare with the differences of throwing motion ,the significant levels was as α = .05. The results were : 1.overarm throw Motion: the phrase from the ball accelerating to ball released from hand demonstrate a larger angle of lateral trunk tilt, the maximum angular velocity of the front trunk tilt and the largest angle of shoulder abduction. When the ball is released, there will be a greater angular velocity of forefoot knee joint and shoulder axis angle would tend toward non-dominant hand of the player. 2.Sidearm throw Motion: in the phase of acceleration, the Maximum trunk rotation angular velocity becomes greater. When the ball is released, there will be greater COM velocity and upward of velocity. And, the shoulder axis angle tends toward the front of the player. 3.Overarm throw with stepping in motion: the phrase from the ball accelerating to ball released from hand demonstrate a larger angle of lateral trunk tilt, the maximum angular velocity of the front trunk tilt and the largest angle of shoulder abduction. When the ball is released, there will be a greater angular velocity of forefoot knee joint and shoulder axis angle would tend toward non-dominant hand of the player. 4.Sidearm throw with stepping in motion: In the phrase of preparation, the player might have a longer percentage of the strike length; in the phase of acceleration, the player might have a larger displacement of the whole gravity and displacement in the direction of moving forwards. The trunk rotation angular velocity also becomes greater. When the ball is released, there will be a greater velocity of COM upward and angular velocity of shoulder internal rotation. Suggestions: As for the sports performance, sidearm throw with stepping in motion leads to the faster ball Velocity, the player who steps in motion has a longer time to control the ball; as for the risk of injury, the larger trunk lateral bending angle and shoulder abduction angle caused by overarm throw have a negative impact on the pressure of the elbow valgus.