高中110公尺跨欄選手前後腳換位起跑之生物力學分析

Abstract

本研究目的：探討高中男子 110 公尺跨欄選手使用前後腳換位起跑動力學參數之間的差異。方法：以8 位高中欄架選手為研究對象（身高179.62±5.04公分，體重為70.63±5.55及年齡17.87±0.99歲）。依平衡次序原則，進行兩種不同起跑（七步、八步） 測驗。資料收集部分：實驗儀器為兩部 (JVC) 高速數位攝影機(120Hz)，架設於垂直動作平面上，收集受試者左側矢狀面從起跑預備動作、起跑推蹬階段與起跑七步出發及起跑八步出發跨過前三道欄架之影像動作。運動學參數以 Kwon3D 動作進行分析。統計方法以無母數統計魏可遜(Wilcoxon)符號等級考驗進行各項參數差異之檢定。結果：一、七步起跑及八步起跑在起跑反應時間為( 0.21±0.04 min、0.20±0.03 min )，前腳及後腳推蹬踏板時間為( 0.33±0.05 min、0.29±0.01 min；0.21±0.03 min、0.19±0.01 min )，前腳及後腳離板時間為 ( 0.41±0.05 min、0.38±0.02 min；0.36±0.06 min、0.36±0.04 min)，起跑至跨過第一道欄架時間為( 2.50±0.23 min、2.45±0.10 min )，起跑至跨過第三道欄架時間為( 5.44±0.27 min、5.38±0.13 min )，以上參數結果均無顯著差異。二、起跑後前七步著地時之步幅、跨過第一道欄架落地後欄間步幅、跨過第二道欄架落地後欄間步幅，起跑七步組均顯著高於起跑八步組。三、起跑後第一步至第七步著地重心水平、垂直速度與合速度、起跑後跨過前三道欄架重心位移均達顯著差異。本研究發現七步起跑技術較適合身高達到一定水準以上之選手適用，建議教練與選手可嘗試起跑七步出發新技術，以利提升國內競技跨欄水準。This study aims to analyze mechanic parameter differences on start of high school racer of 110m hurdles by 8 high school hurdles racer (Height: 179.62±5.04cm; Weight: 70.63±5.55kg; age: 17.87±0.99years). Based on counterbalancing method, the participants had been divided into 7 and 8 hurdles step groups. The kinematics data collected by using 2 JVC high speed digital cameras, the first camera was collecting the data from the block to the first hurdle, the second camera was filming the movements from the second and the third hurdles. The kinematics variables were analyzed by Kwon 3D software. The Wilcoxon matched-pairs signed-rank nonparametric statistical test was used to compare two different start steps movements by using the SPSS 21.0 software at α = .05 significant level. The result showed that there was no significant difference between 7 and 8 step groups on the reaction time (0.21±0.04 min、0.20±0.03 min ), propulsive time of each leg (0.33±0.05 min、0.29±0.01 min；0.21±0.03 min、0.19±0.01 min ), time of leaving starting block (0.41±0.05 min、0.38±0.02 min；0.36±0.06 min、0.36±0.04 min), time from start to 1st hurdle (2.50±0.23 min、2.45±0.10 min) and time from start to 3rd hurdle (5.44±0.27 min、5.38±0.13 min).The 7-step were superior to the 8-step on step length of start, 1st hurdle, 2nd hurdle. The significant differences also found on the horizontal center-of-gravity, vertical velocity, resultant velocity of the first three hurdles on the 1 to 7 step after starting. We found that the taller hurdler performed the better result while using the 7 step start. Suggest hurdles coach and racer can try 7-step hurdle to improve the hurdle record.