背景: 進行第一回合離心運動（100%EC1）間隔數週休息後，改換成對側相同肌群進行相同一回合離心運動 （100%EC2）時，可以使肌肉損傷明顯比100%EC1變小。然而，目前文獻不清楚人體以某一側肘屈肌群EF）進行五回合漸增離心訓練後，是否也可以有效降低另一側EF進行一回合100%EC引起肌肉損傷的效果。因此，本研究目的針對「人體先以某一側EF先進行五回合漸增強度離心訓練對刺激另一側EF對抗一回合100%EC時，降低引起肌肉損傷之交叉重複訓練效果做探討。方法：以隨機分配方式將 18名無接受訓練之健康成年男子分至控制組與實驗組之中（n＝9/組）。控制組以平衡次序先讓某一側EF進行一回合30次100%EC後第7天時，再改換成對側EF進行另一回合30次100%EC；實驗組先以非慣用側EF（ND-EF）接受每週一回合30次連續五週的漸增式離心訓練 (強度：10%-100%EC)，間隔休息一週後，再換成慣用側EF（D-EF）進行一回合100%EC。最大等長收縮肌力 (MVC)、關節活動範圍 (ROM)、肢體圍 (CIR) 和肌肉酸痛 (SOR) 在每回合離心運動前至運動後第3或5天進行觀察，並以二因子混合設計變異數分析考驗依變項在組別與時間之間的差異。結果：實驗組ND-EF完成五週離心訓練後，改用D-EF進行一回合100%EC引起的MVC、ROM、CIR和SOR的變化程度都明顯比控制組進行100%EC1與100%EC2來得小（p < .05）。結論：這些研究結果顯示，先讓ND-EF進行5回合漸增離心訓練後，可有效降低D-EF進行一回合100%EC引起肌肉損傷之效果。
關鍵詞： 阻力運動訓練、最大自主等長收縮肌力 (MVC)、肌肉酸痛 (SOR)、關節活動範圍 (ROM)、肢體圍 (CIR)

BACKGROUND: An initial bout of 100% eccentric exercise (100%EC) can significantly attenuate muscle damage following a second bout of the same eccentric exercise (100%EC2) performed with the same muscle group on the opposite side of the body after a few weeks of rest. However, it is currently unclear whether performing five bouts of progressive eccentric exercise with the elbow flexors (EF) before performing one bout of 100%EC with the opposite EF can reduce muscle damage. Thus, the purpose of this study was to investigate whether a contralateral repeated bout effect is manifested after performing five bouts of progressive eccentric exercise with one EF, thus reducing muscle damage caused by one bout of 100%EC with the opposite EF. METHODS: Eighteen untrained healthy men were randomly assigned to control and experimental groups (n=9/group). The control group used one EF to perform a bout of 30 100%EC, before performing a second bout of 30 100%EC with the opposite EF 7 days later. The experimental group used the non-dominant EF (ND-EF) to perform a bout of 30 progressive eccentric training exercises (intensity: 10%-100%EC) once a week for five consecutive weeks, followed 1 week later by a bout of 100%EC with the dominant EF (D-EF). Maximal voluntary isometric contraction strength (MVC), range of motion (ROM), circumference (CIR) and muscle soreness (SOR) were measured before, immediately after, and 3 or 5 days after exercise. Data were compared by repeated-measures of two-way ANOVA, analyzing the differences between group and time of the dependent variables. RESULTS: After the five-week eccentric training with the ND-EF for the experimental group, changes in MVC, ROM, CIR and SOR of the D-EF following one bout of 100%EC were significantly smaller than those of the control group, which performed 100%EC1 and 100%EC2 (p<.05). CONCLUSIONS: These results have shown that five bouts of progressive eccentric training with the ND-EF can effectively reduce the extent of muscle damage caused by one bout of 100% EC with the D-EF.

Keywords: resistance training, maximal voluntary isometric contraction strength (MVC), muscle soreness (SOR), range of motion (ROM), circumference (CIR)

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