投擲練習前後足底壓力變化之比較

The Comparison of Plantar Pressure Before and After Practice for Throwing

緒論：成長過程中的任何技能，都是經由長時間練習而來的，投擲動作也是如此，對於發展學童而言，練習對於學童而言顯得相當重要。本研究在於瞭解國小男童在過肩投擲八週訓練前後手臂向前揮動初期軸心腳與球體離手瞬間之引導腳，分別在前足區 (細分為五區)、中足區及後足區上的壓力分佈差異以及壓力中心走向之差異。方法：以19名國小學童為參與者，透過Medilogic測力鞋墊 (60Hz) 及其分析軟體 (Medilogic 3.8版) 配合攝影機 (JVC 9800, 60Hz)，以Medilogic系統內建FAp-video軟體同步紀錄動作，並以相依樣本t考驗分析。結果：國小男童訓練後在向前揮動初期軸心腳的壓力區由足跟區轉而集中在前足區，並達到顯著差異；而球體離手期引導腳的壓力區亦由足跟區變為集中至前足區，同樣達顯著差異。男童練習前和練習後的離手球速有顯著差異，且練習後的離手球速優於練習前；且足壓中心走向分布圖有差異，XY軸範圍皆擴大。結論：本研究結果發 現男童訓練後足壓分佈明顯不同、壓力中心向前移動趨勢明顯，顯示可見充分的練習確實有助於運動表現的進步，建議國小體育教師進行投擲相關課程教學時觀察學童投擲動作型態再予以指導，並加入引導腰部旋轉訓練與軀幹前傾動作。

 

A long period of practicing time can make easily master a skill. So does the action of throwing, especially for children. The effect of throw practicing is even more important than any other stages of growing. Hence, the purposes of this study was to understand of the practice effect of the overarm throwing from foot plantar pressure distribution. Nineteen (elementary school students) were recorded the overarm throwing motion by high-speed camera (JVC 9800, 60Hz) with wearing pressure sensor insole. The paired-T test was used to analyze the difference of pre- and post-practice of the overarm throwing. The test result showed a significant increased after practicing. The pressure area move from heels to forefoot after practice when compared with before practice. The speed of ball throwing was greater than it was before practicing. In conclusion, this study found that after the overarm throwing practicing, the obvious change of foot pressure distribution from heels to forefoot. It was help teachers to instruct students learning overarm throwing.