J Sport Rehabil. 2020 Oct 12;30(3):482-491. doi: 10.1123/jsr.2019-0388.
Nordic hamstring exercise (NHE) has been widely employed to prevent hamstring strain injuries. However, it is still not clear which adaptations are responsible for the NHE preventive effects.
The aim of this study was to investigate the effects of NHE on knee flexors eccentric strength and fascicle length.
The search strategy included MEDLINE, PEDro, and Cochrane CENTRAL from inception to April 2020. Randomized clinical trials that have analyzed the effects of NHE training on hamstring eccentric strength and/or fascicle length were included.
From the 1932 studies identified, 12 were included in the systematic review, and 9 studies presented suitable data for the meta-analysis. All studies demonstrated strength increments in response to NHE training (10%-15% and 16%-26% in tests performed on the isokinetic dynamometer and on the NHE device, respectively), as well as significant enhancement of biceps femoris long head fascicle length (12%-22%). Meta-analysis showed NHE training was effective to increase knee flexors eccentric strength assessed with both isokinetic tests (0.68; 95% confidence interval, 0.29 to 1.06) and NHE tests (1.11; 95% confidence interval, 0.62 to 1.61). NHE training was also effective to increase fascicle length (0.97; 95% confidence interval, 0.46 to 1.48).
NHE training has the potential of increasing both knee flexors eccentric strength and biceps femoris long head fascicle length.
北欧腘绳肌训练（NHE）已被广泛用于预防腘绳肌拉伤。然而，NHE 的预防效果所对应的适应机制仍不清楚。
本研究旨在探究 NHE 对膝关节屈肌离心力量和肌束长度的影响。
检索策略包括从建库至 2020 年 4 月的 MEDLINE、PEDro 和 Cochrane 中心数据库。纳入分析 NHE 训练对腘绳肌离心力量和/或肌束长度影响的随机临床试验。
从最初确定的 1932 项研究中，有 12 项研究被纳入系统综述，9 项研究提供了适合 meta 分析的数据。所有研究均表明，NHE 训练可增强力量（在等速测力计和 NHE 设备上的测试中分别增加 10%-15%和 16%-26%），并显著增加股二头肌长头肌束长度（12%-22%）。meta 分析显示，NHE 训练可有效增加等速测试（0.68；95%置信区间，0.29 至 1.06）和 NHE 测试（1.11；95%置信区间，0.62 至 1.61）评估的膝关节屈肌离心力量。NHE 训练还可有效增加肌束长度（0.97；95%置信区间，0.46 至 1.48）。
NHE 训练有增强膝关节屈肌离心力量和股二头肌长头肌束长度的潜力。
