Department of Physical Education, National Taiwan Normal University, Taipei City, TAIWAN.
Med Sci Sports Exerc. 2018 Mar;50(3):542-550. doi: 10.1249/MSS.0000000000001470.
Eccentric exercise of the elbow flexors (EF) confers protective effect against muscle damage of the same exercise performed by the opposite arm at 1, 7, or 28 d later. This is known as the contralateral repeated bout effect (CL-RBE), but it is not known whether CL-RBE is evident for the knee flexors (KF). The present study tested the hypothesis that KF CL-RBE would be observed at 1, 7, and 28 d after the initial bout.
Young untrained men were assigned to a control or one of three experimental groups (n = 13 per group). The experimental groups performed 60 maximal KF eccentric contractions (60MaxEC) using one leg followed by the same exercise using the opposite leg at 1, 7, or 28 d later. The control group used the nondominant leg to repeat 60MaxEC separated by 14 d. Changes in several indirect muscle damage markers after 60MaxEC were compared between bouts and among the groups by using a mixed-design, two-way ANOVA.
Changes in maximal voluntary isokinetic concentric contraction torque, range of motion, muscle soreness, and plasma creatine kinase activity after the first 60MaxEC were similar among the groups. These changes were smaller after the second than the first 60MaxEC for the control, 1-d, and 7-d groups, and the changes after the second 60MaxEC were smaller for the control than for both the 1- and 7-d groups (P < 0.05). When the KF CL-RBE was compared with the EF CL-RBE of the previous study, the magnitude was not significantly different.
These results showed that CL-RBE was evident for KF in a similar manner to that for EF, but did not last for 28 d, and the CL-RBE was smaller than the ipsilateral RBE.
对侧臂在 1 天、7 天或 28 天后进行相同的肘部屈肌（EF）偏心运动可产生对肌肉损伤的保护作用。这种现象被称为对侧重复运动效应（CL-RBE），但膝屈肌（KF）是否存在 CL-RBE 尚不清楚。本研究旨在检验以下假设：在初次运动后 1、7 和 28 天，KF 的 CL-RBE 将会出现。
将未训练的年轻男性分为对照组和三个实验组（每组 13 人）。实验组的一条腿进行 60 次最大 KF 离心收缩（60MaxEC），然后在 1、7 或 28 天后对另一条腿进行相同的运动。对照组使用非优势腿在 14 天间隔内重复 60MaxEC。采用混合设计双向方差分析比较两批运动之间和各组之间 60MaxEC 后几种间接肌肉损伤标志物的变化。
初次 60MaxEC 后，各组的最大等速向心收缩扭矩、运动幅度、肌肉酸痛和血浆肌酸激酶活性的变化相似。与对照组、1 天组和 7 天组相比，第二次 60MaxEC 后的变化较小，与 1 天组和 7 天组相比，对照组的变化较小（P < 0.05）。与之前研究中的 EF-CL-RBE 相比，KF-CL-RBE 的幅度没有显著差异。
这些结果表明，KF 的 CL-RBE 与 EF 相似，但持续时间不超过 28 天，且 CL-RBE 小于同侧 RBE。
