兩組不同等級標槍選手之生物力學分析
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2006
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Abstract
本研究希望透過兩組不同水準選手之比較，除了找出動作技術的關鍵點也幫助一般選手更進一步。受試者為大專男子選手，優秀選手組最佳紀錄平均為68.04±5.68 m，一般選手組為55.74±7.17 m。利用四台同步之Redlake高速攝影機（兩台125 Hz拍攝人體動作，另兩台250 Hz拍攝槍體）與一塊Kistler測力板（1250 Hz）來擷取資料；以Kwon 3D軟體處理資料並以Butterworth 4th order修勻（6 Hz）。以三維動力學逆過程計算槍體及下肢各關節受力情形，槍體受力程式以Matlab 6.5版來執行。經由比較分析後發現：
（一）優秀選手出槍前最大軸向力平均194.6±19.6 N，一般選手平均為147.81±18.54 N，優秀選手顯著地大於一般選手。（二）優秀選手前後傾的角度比一般選手來得大，另外成績越好的選手肩關節的角速度也有越大的現象。（三）制動腳剛著地時，優秀選手之左膝角度（166.3±4.9 deg）顯著地大於一般選手（154.4±10.4 deg）。另外助跑時身體質心速度方面，不管是在推蹬腳著地、制動腳著地及出槍時優秀選手之身體速度皆顯著地大於一般選手（四）標槍在腳跟剛著地時地面反作用力會急速上升，造成一2000 ~ 2222 N左右的最大垂直力量峰值；且由測力板之前後分力來看，出槍瞬間是發生在制動期階段，非推蹬期階段。
By analysis of the two levels of javelin throwers, the purpose of this study was: (1) To find the keys of throwing technique. (2)To make the general group better. All subjects are college throwers, the mean personal record of elite group is 68.04±5.68 m, and that of general group is 55.74±7.17 m. Two Redlake cameras (125 Hz) for throwing motion, and another two Redlake cameras (250 Hz) for javelin motion and a synchronized force plate (Kistler, 1250 Hz) were used to collect the data. The data were digitized by Kwon 3D software and smoothed by Butterworth 4th order with 6 Hz cut-off frequency. The 3D inverse dynamics was analyzed with the force applied to the javelin and in lower extremity. The results included: (1) The axial force of elite group (194.6±19.6 N) was significant larger than that of general group (147.81±18.54 N)。(2)The elite group had a significant larger left hip flexion than the general during throwing, and there was a significantly positive correlation between the shoulder angular velocity and flight distance. (3)The angle of left knee of the elite group (166.3±4.9 deg) was significantly larger than that of the general group(154.4±10.4 deg) while the left heel touched the ground. At the time of last left foot landing, right foot landing and release, the run-up speed of elite group was significantly faster than that of the general. (4) The vertical GRF was dramatically increase to the peak (about 2000~2200 N) just at the moment that the left heel touched the ground. According to the pattern of forward horizontal force of GRF, the javelin release occurred in the braking phase.
By analysis of the two levels of javelin throwers, the purpose of this study was: (1) To find the keys of throwing technique. (2)To make the general group better. All subjects are college throwers, the mean personal record of elite group is 68.04±5.68 m, and that of general group is 55.74±7.17 m. Two Redlake cameras (125 Hz) for throwing motion, and another two Redlake cameras (250 Hz) for javelin motion and a synchronized force plate (Kistler, 1250 Hz) were used to collect the data. The data were digitized by Kwon 3D software and smoothed by Butterworth 4th order with 6 Hz cut-off frequency. The 3D inverse dynamics was analyzed with the force applied to the javelin and in lower extremity. The results included: (1) The axial force of elite group (194.6±19.6 N) was significant larger than that of general group (147.81±18.54 N)。(2)The elite group had a significant larger left hip flexion than the general during throwing, and there was a significantly positive correlation between the shoulder angular velocity and flight distance. (3)The angle of left knee of the elite group (166.3±4.9 deg) was significantly larger than that of the general group(154.4±10.4 deg) while the left heel touched the ground. At the time of last left foot landing, right foot landing and release, the run-up speed of elite group was significantly faster than that of the general. (4) The vertical GRF was dramatically increase to the peak (about 2000~2200 N) just at the moment that the left heel touched the ground. According to the pattern of forward horizontal force of GRF, the javelin release occurred in the braking phase.
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標槍, 三維動力學逆過程, 軸向力, Javelin, 3D Inverse dynamics, Axial force