Almosnino Sivan, Pelland Lucie, Pedlow Samuel V, Stevenson Joan M
School of Rehabilitation Therapy, Queen's University, Kingston, ON, Canada.
Sports Med Arthrosc Rehabil Ther Technol. 2009 Sep 23;1(1):22. doi: 10.1186/1758-2555-1-22.
The purpose of this study was to assess the between-day reliability of the electromechanical delay (EMD) of selected neck muscles during the performance of maximal isometric contractions in five different directions.
Twenty-one physically active males participated in two testing sessions separated by seven to eight days. Using a custom-made fixed frame dynamometer, cervical force and surface electromyography (EMG) were recorded bilaterally from the splenius capitis, upper trapezius and sternocleidomastoid muscles during the performance of efforts in extension, flexion, left and right lateral bending, and protraction. The EMD was extracted using the Teager-Kaiser Energy Operator. Reliability indices calculated for each muscle in each testing direction were: the difference in scores between the two testing sessions and corresponding 95% confidence intervals, the standard error of measurement (SEM) and intra-class correlation coefficients (ICC).
EMD values showed no evidence of systematic difference between the two testing sessions across all muscles and testing directions. The SEM for extension, flexion and lateral bending efforts ranged between 2.5 ms to 4.8 ms, indicating a good level of measurement precision. For protraction, SEM values were higher and considered to be imprecise for research and clinical purposes. ICC values for all muscles across all testing directions ranged from 0.23 to 0.79.
EMD of selected neck muscles can be measured with sufficient precision for the assessment of neck muscle function in an athletic population in the majority of directions tested.
本研究的目的是评估在五个不同方向进行最大等长收缩时，所选颈部肌肉的机电延迟（EMD）的日间可靠性。
21名身体活跃的男性参加了两次测试，两次测试间隔7至8天。使用定制的固定框架测力计，在进行伸展、屈曲、左侧和右侧侧弯以及前伸动作时，双侧记录头夹肌、上斜方肌和胸锁乳突肌的颈部力量和表面肌电图（EMG）。使用Teager-Kaiser能量算子提取EMD。在每个测试方向上为每块肌肉计算的可靠性指标包括：两次测试之间得分的差异以及相应的95%置信区间、测量标准误差（SEM）和组内相关系数（ICC）。
在所有肌肉和测试方向上，两次测试之间的EMD值均未显示出系统差异的证据。伸展、屈曲和侧弯动作的SEM在2.5毫秒至4.8毫秒之间，表明测量精度良好。对于前伸动作，SEM值较高，从研究和临床目的来看被认为是不精确的。所有肌肉在所有测试方向上的ICC值在0.23至0.79之间。
对于大多数测试方向上的运动员群体，所选颈部肌肉的EMD可以以足够的精度进行测量，以评估颈部肌肉功能。
