低強度離心運動對重複訓練效應及表層肌電訊號活性之影響

Effects of Low-Intensity Eccentric Exercise on Repeated Bout Effect and Surface Electromyographic Activity

曾暐晉(Wei-Chin Tseng) ； 曾國維(Kuo-Wei Tseng) ； 陳信良(Hsin-Lian Chen) ； 陳忠慶(Trevor Chung-Ching Chen)

《物理治療》 41卷3期 (2016/09) Pp. 189-198

https://doi.org/10.6215/FJPT.PTS1455547793

摘要

背景與目的：人體單側膝伸肌群(knee extensors, KE)預先進行一回合低強度離心運動(10% eccentric contractions, 10%EC)不會引起肌肉損傷，但可在隨後7天內繼續進行一回合最大離心運動(maximal eccentric contractions, MAX)時，有效降低肌肉損傷現象，相關文獻推測可能與神經因素有關。因此，研究目的針對上述假設做探討。方法：一群健康男性成人隨機分成實驗與控制組(11人／組)。實驗組以非慣用腿KE做60次10%EC後1週，繼續做60次MAX；CON僅以非慣用腿KE做60次MAX。比較兩組研究對象在做MAX前、中、後第0 ~ 5天之數個肌肉損傷或肌電圖指標。結果：實驗組在10%EC後，所有依變項均未產生顯著變化，但是在隨後進行MAX時，卻有效使肌力、肌肉酸痛與血液肌酸激酶活性的變化程度明顯比控制組的MAX來得小。實驗組在MAX時的均方根肌電訊號值與運動壓力值分別比控制組在MAX時來得大與小，但兩組的力矩峰值和平均數功率頻率則無差異。結論：此研究結果顯示，10%EC有效降低隨後進行MAX引起肌肉損傷效果，可能是藉由神經適應因素引起的。

關鍵字

最大等速離心收縮 ； 預先運動訓練效應 ； 非肌肉損傷運動 ； 延遲性肌肉酸痛 ； 神經適應

並列摘要

Background and purpose: Preconditioning exercise consisting of low-intensity eccentric exercise (10%EC) of the knee extensors (KE) does not induce signifi cant muscle damage, but can attenuate the extent of muscle damage induced by subsequent maximal isokinetic eccentric exercise (MAX) performed within 7 days later. Previous researchers have speculated that this effect could possibly be due to neural adaptations. Thus, the present study investigated the above hypothesis. Methods: A group of untrained healthy young men were randomly placed into experimental or control (N = 11/group) group. The experimental group performed 60 eccentric contractions with a loading of 10% maximal voluntary isometric contraction strength (10%EC) followed by 60 MAX of the KE of the non-dominant leg performed one week later. The control group performed only a bout of 60 MAX using the non-dominant KE. Several muscle damage or electromyography markers were measured before, during, and for 5 consecutive days post each exercise. Results: The results showed that: (1) None of the variables showed significant changes following 10%EC (p ＞ 0.05) for the experimental group, but the 10%EC still attenuated the extent of muscle damage (strength, soreness, plasma creatine kinase activity) induced by subsequent MAX performed one week later; (2) Although peak torque and mean power frequency during MAX did not show a significant difference between the experimental and control groups, the extent of root-mean square and MAX stress ratio during MAX for the experimental group was significantly (p ＜ 0.05) greater and smaller, respectively, than during MAX for the control group. Conclusion: These results suggest that a bout of preconditioning exercise of 10%EC of the KE could efficiently attenuate muscle damage induced by subsequent MAX performed one week later by neural adaptation factors.

並列關鍵字

Maximal voluntary isokinetic eccentric contractions ； Preconditioning effect ； Non-damaging exercise ； Delayed onset muscle soreness ； Neural adaptation