在分析最佳迴轉速的文獻中,發現最佳迴轉速大約是90rpm,這些的研究是以肌肉活性EMG和生理學的方式測量,卻很少有研究是用中間頻率實驗。因此,本實驗的研究目的為受試者在固定的功率200w下,在6min的自由車運動中,比較由肌肉EMG活性值的百分比所測得的最佳迴轉速是否與EMG中間頻率下降程度所預測的最佳迴轉速相同。研究對象為3位參與自由車公路賽訓練的男性運動員。本實驗使用Noraxon MyoResearch XP肌電訊號系統取得(1500Hz)資料,本實驗由亂數表排列60、70、80、90、100、110rpm迴轉速的次序,每個迴轉速以200w的輸出功率騎6min,中間休息15min,分析2min~3min和5min~6min的EMG活性百分比,以及分析2min~6min的EMG中間頻率下降程度;本實驗結果為,這三位受試者在輸出功率200w,迴轉速60~110rpm的實驗中,最小的EMG活性皆為60rpm;而EMG中間頻率下降不明顯。本研究結論為,從EMG活性百分比來看三位受試者最小活性值皆出現在60rpm,為這三位受試者個人的最佳迴轉速,EMG中間頻率分析無法測得個人最佳回轉速可能是因為肌肉尚未達到足夠的疲勞。
The analysis of preferred cadence in previous literatures was 90rpm. These studies examined muscle activity with IEMG and physiological methods to measure the cadence. There were few literatures using the median frequency. Thus, the purpose of this study was to examine the consistency of the prediction of preferred cadence between EMG activity and median frequency. The subjects were 3 male cyclists. Noraxon MyoResearch XP EMG signal analysis system was used in this study. The order of cadence was arranged using random number table (60, 70, 80, 90, 100, 110rpm). The subject rode bike for 6min at 200w power output. The resting time between testing cadence was 15 min. The data were analyzed using EMG activity between 2~3 min and 5~6 min and EMG median frequency between 2~ 6min. The results of this study are as follows. These subjects` have lowest EMG activity at 60 rpm when the output was at 200w and cadence was between 60 to 110rpm. The EMG median frequency analysis didn`t reduce significantly. The conclusions of this study are as follows. Those subject`s preferred cadence were 60 rpm that analysis from the lowest EMG activity when output at 200w and cadence between 60 to 110rpm. The EMG median frequency analysis didn`t have significant reduction. Because the muscles didn`t fatigue enough for the median frequency reduction.