肘屈肌群離心運動對肌肉肌腱複合體之影響

Abstract

背景：先前研究顯示，肘屈肌群進行離心運動後會引起明顯肌纖維細微損傷 (EIMD)之現象，但目前尚未知道EIMD是否會影響肌肉肌腱複合體之變化。目的：考驗「肘屈肌群進行單一回合最大離心運動，是否會對肌肉肌腱複合體造成影響」，以及釐清「離心運動引起肌肉損傷，是否會與肌肉肌腱複合體的改變有關」等假設。方法：招募20名未接受訓練的健康男性做為研究對象，並以其非慣用手肘屈肌群進行一回合5組 x 6次最大等速 (30°/s) 離心收縮運動。在進行離心運動前及運動後第1~5天，讓研究對象各進行一次CIR、SOR、RANG、CK與超音波 (肌肉肌腱長度) 等指標之觀察，並以單因子重複量數變異數分析及皮邇遜積差相關進行統計分析。結果:與前測值相比，所有依變項均產生明顯的變化 (p<.05)。離心運動後引起最大肌腱變化程度與CIR (r = -.79)、CK (r = -.50)、SOR (r = -.72) 以及RANG (r = .76) 之間具有相關 (p <.05)。結論:本研究發現，離心運動不僅引起肌肉損傷，同時也影響肌肉肌腱複合體的改變。因此，肌肉肌腱複合體的改變可能反應在EIMD的強度。BACKGROUND: It is well-documented that eccentric exercise of the elbow flexors results in significant muscle damage, but it is not known whether eccentric exercise-induced muscle damage (EIMD) would be involved with changes in muscle-tendon behaviour of the damaged muscles. PURPOSE: To test the hypothesis that changes in muscle-tendon behaviour following a single bout of maximal eccentric exercise would be associated with EIMD. METHODS: Twenty untrained young men performed 5 x 6 maximal isokinetic (30°/s) eccentric contractions of the elbow flexors of the non-dominant arm to induce muscle damage. Changes in upper arm circumference (CIR), muscle soreness (SOR), relaxed elbow joint angle (RANG), plasma creatine kinase activity (CK), and muscle-tendon behaviour of the long head of biceps brachii of real-time B-mode ultrasound scanning images were taken before, immediately after, and for 5 consecutive days after exercise. Data were compared by repeated-measures of One-way ANOVA repeated measures and Pearson product-moment correlation coefficient. RESULTS: All dependent variables showed significant changes following eccentric exercise compared with baseline levels (p<.05). The maximal changes in muscle-tendon behaviour after eccentric exercise had a correlation with peak-CIR (r = -.79), peak-CK (r = -.50), peak-SOR (r = -.72) and lowest-RANG (r = .76; p <.05). CONCLUSIONS: These results suggested that eccentric exercise induced not only significant muscle damage, but also changes in muscle-tendon behaviour. It appears that changes in muscle-tendon behaviour are likely to be reflected in the magnitude of EIMD.