Department of Physical Therapy, Division of Health Science, Baekseok University, Cheon-an, Republic of Korea.
J Hum Kinet. 2013 Mar 28;36:69-76. doi: 10.2478/hukin-2013-0007. Print 2013 Mar.
The purpose of this study was to examine the test-retest reliability of normalization methods for the infraspinatus muscle in a group of healthy subjects. Twelve healthy subjects (male=8, female=4) performed the maximal voluntary isometric contraction (MVIC) with examiner`s resistance, MVIC with a digital tension-meter (MVIC-DT), and sub-MVIC methods. Surface electromyography (EMG) signals were recorded from the infraspinatus muscles according to normalization methods. Reliability was analyzed using the intra-class coefficient (ICC), standard error of measurement (SEM), and minimal detectable difference (MDD). The results of the present study demonstrated that the sub-MVIC method has excellent test-retest reliability (ICC=0.92) with a relatively small SEM (5.9 mV) and MDD95 (16.4 mV), compared to MVIC-DT (ICC=0.73; SEM=11.2 mV; MDD95: 31 mV) and MVIC-E (ICC=0.5; SEM=15.7 mV; MDD95: 43.6 mV). These findings provide evidence that sub-MVIC is more appropriate for comparing the EMG activity for the infraspinatus muscle as a normalization method. If MVIC for normalization is needed, MVIC-DT is more appropriate than MVIC-E.
本研究旨在检验一组健康受试者中冈下肌肌肉正常化方法的重测信度。12 名健康受试者（男性 8 名，女性 4 名）进行了最大自主等长收缩（MVIC），其中包括与检查者对抗的 MVIC、数字张力计的 MVIC（MVIC-DT）和亚 MVIC 方法。根据正常化方法记录冈下肌的表面肌电图（EMG）信号。使用组内相关系数（ICC）、测量标准误差（SEM）和最小可检测差异（MDD）分析可靠性。本研究的结果表明，与 MVIC-DT（ICC=0.73；SEM=11.2 mV；MDD95：31 mV）和 MVIC-E（ICC=0.5；SEM=15.7 mV；MDD95：43.6 mV）相比，亚 MVIC 方法具有极好的重测信度（ICC=0.92），其 SEM（5.9 mV）和 MDD95（16.4 mV）相对较小。这些发现为亚 MVIC 作为一种正常化方法更适合比较冈下肌肌电图活动提供了证据。如果需要 MVIC 进行正常化，MVIC-DT 比 MVIC-E 更合适。
