創新設計之動態轉動慣量網球拍對揮拍速度與主觀感受之立即性影響

Abstract

目的 : 正拍擊球為現代網球主流，揮拍速度是正拍擊的關鍵因素之一，因此本研究目的為利用動態轉動慣量之概念，設計創新的揮拍速度訓練用網球拍 (以下稱 : DMOI球拍) ，驗證 (一) 使用 DMOI球拍進行揮拍訓練後對揮拍速度之立即影響； (二) 使用DMOI球拍之主觀感受。方法 : 本研究徵召共 26名大專層級的甲組球員與乙組球員，分別進行DMOI球拍與一般球拍之揮拍，在使用前後進行加速初期速度、加速後期速度、以及揮拍主觀感受等測試。使用重複量數二因子變異數分析、依相依樣本 t檢定比較相關參數。結果 : 當前研究發現 (一) 甲組與乙組使用 DMOI球拍揮拍訓練後，於加速初期與加速後期均顯著增加立即揮拍速度； (二) 甲組揮擊 DMOI球拍主觀感受於流暢滿意度項目滿意度顯著低於一般球拍，乙組揮擊DMOI球拍主觀感受於加速初期省力度顯著高於一般球拍。結論 : 在經過 DMOI球拍訓練後，相較一般球拍訓練，甲組與乙組選手均更能有效增加揮拍速度。因此，建議 DMOI球拍可做為提升大專網球球員揮拍速度的訓練器材之一。  Purpose: Forehand strike is the main strategy in the contemporary era, enhance the forehand strike must to shorten the swing speeds, therefore the purposes of this study were to design and construct the novel Dynamic Moment of Inertia (DMOI) racquet, as well as to investigate (1) The acute effects of DMOI racquet on swing velocity. (2) Subjective perceived by using the DMOI racquet. Methods: 26 college tennis players in Division I (D1) and in Division II (D2) tennis players were participated in the study and swung the DMOI and normal racquets respectively in balance order. Two photocell time gate were used to detect the swing velocities at first acceleration phase and second acceleration phase. The subjective perceived scale was tested after velocity test. Results: D1 and D2 after statistical analysis of the dependent t-test respectively, (1) both college tennis players in D1 and D2 were significantly higher swing velocities after using DMOI racquet. (2) the college tennis players in D2 Group has higher subjective perceived score on swing with saving effort at early acceleration phase compared to that of the normal racquet. Conclusion: In swing aspect, the DMOI racquet after training programed have faster swing velocity and has positive acute effect on swing velocities compared to those of the normal racquet. Therefore, the DMOI racquet could be a useful training equipment for improving swing velocity.