研究目的:探討引體向上時,雙手肌群正、反握槓在不同握槓寬度時之表現差異。研究方法:採用肌電圖觀察三種不同抓槓距離(併攏、與肩同寬、肩膀寬長1.5倍)在正、反握時,對於八個肌群影響,進行積分肌電討論。結果:得知屈腕肌於六種動作模式中,IEMG皆爲最大值,最大值達1.87%.s(正握與肩1.5位寬時),因此爲引體向上主要肌群;伸腕肌於六種動作模式時,IEMG皆爲次大,最大IEMG達0.51%.s(正握與肩1.5位寬時),因此爲引體向上之輔助肌群。而六種動作模式中發現,正握與肩1.5倍寬各肌群可達其IEMG最大值,較具訓練效果,其次要作用肌群有肱三頭肌0.39%.s、闊背肌0.36%.s、胸大肌0.35%.s及肱二頭肌0.33%.s。結論:建議可採正握與肩1.5倍寬引體向上訓練肌力最有效率,以正握與肩同寬握槓方式則較適合訓練上肢肌耐力。
Purpose: This study is to explore the difference in muscle groups of both hands when both hands grasp at the horizontal bar in chinning up exercise with the following six gestures: 1. overhand grip and both hands gathering together; 2. overhand grip and both hands a shoulder width apart; 3. overhand grip and both hands 1.5 times the shoulder width apart; 4. underhand grip and both hands gathering together; 5. underhand grip and both hands a shoulder width apart; 6. underhand grip and both hands 1.5 times the shoulder width apart. Method: According to EMG and IEMG, this study will explore the different results of the eight primary muscle groups when they are under the 6 conditions mentioned above. Result: Under the six conditions, wrist Flexors get the highest IEMG points respectively, with a maximum of IEMG1.87%.s. Thus, it is concluded that wrist Flexors are the major muscle group. Wrist Flexors follow behind wrist extensors, with a maximum of IEMG 0.51%.s, which indicates that wrist extensors are the minor muscle group. Among the six conditions, all muscle groups reach their highest IEMG points when overhand grip and both hands are 1.5 times the width of shoulders apart (condition 3); therefore, it is more efficient in training muscles if this gesture is performed. The statistics of such training gesture are as following-wrist flexors: IEMG 1.87%.s; wrist extensors: IEMG 0.51%.s; triceps: IEMG 0.39%.s; latissimus dorsi: IEMG 0.36%.s; pectoralis stemal: IEMG 0.35%.s; biceps brachii: IEMG 0.33%.s. Conclusion: The most efficient way to tain muscle strengh in doing chinning up is the gesture of grasping at the horizontal bar with overhand grip and both hands 1.5 times the shoulder width apart. To train muscle endurance of the upper limbs, it is more suggested to perform the gesture of grasping with fingers towards outside and both hands shoulder wide apart.