Centre for Exercise and Sports Science Research (CESSR), School of Medical and Health Sciences, Edith Cowan University, Perth, WA, Australia.
Centre for Physical Activity and Life Sciences, The University of Northampton, Northampton, UK.
Scand J Med Sci Sports. 2021 May;31(5):1009-1025. doi: 10.1111/sms.13920. Epub 2021 Mar 23.
"Flexibility" tests are traditionally performed voluntarily relaxed by rotating a joint slowly; however, functional activities are performed rapidly with voluntary/reflexive muscle activity. Here, we describe the reliabilities and differences in maximum ankle range of motion (ROM ) and plantar flexor mechanical properties at several velocities and levels of voluntary force from a new test protocol on a commercially available dynamometer. Fifteen participants had their ankle joint dorsiflexed at 5, 30, and 60° s in two conditions: voluntarily relaxed and while producing 40% and 60% of maximal eccentric torque. Commonly reported variables describing ROM and resistance to stretch were subsequently calculated from torque and angle data. Absolute (coefficient of variation (CV%) and typical error) and relative (ICC ) reliabilities were determined across two testing days (≥72 h). ROM relative reliability was good in voluntarily relaxed tests at 30 and 60° s and moderate at 5° s , despite CVs ≤ 10% for all velocities. Tests performed with voluntary muscle activity were only reliable when performed at 5° s , and ROM reliability was moderate and CV ≤ 8%. For most variables, the rank order of participants differed between the slow-velocity, relaxed test, and those performed at faster speeds or with voluntary activation, indicating different information. A person's flexibility status during voluntarily relaxed fast or active stretches tended to differ from their status in the traditional voluntarily relaxed, slow-velocity test. Thus, "flexibility" tests should be completed under conditions of different stretch velocity and levels of muscle force production, and clinicians and researchers should consider the slightly larger between-day variability from slow-velocity voluntarily relaxed tests.
“灵活性”测试通常是在关节缓慢旋转的情况下自愿放松进行的；然而，功能活动是通过自愿/反射性肌肉活动快速进行的。在这里，我们描述了一种新的测试协议在商业上可用的测力计上进行的踝关节最大活动范围（ROM）和跖屈肌机械特性在几个速度和自愿力水平下的可靠性和差异。15 名参与者的踝关节背屈在 5、30 和 60°/s 下进行了两种情况：自愿放松和产生 40%和 60%最大离心扭矩时。随后从扭矩和角度数据计算出通常用于描述 ROM 和抗拉伸性的变量。在两天的测试中（≥72 小时）确定了绝对（变异系数（CV%）和典型误差）和相对（ICC）可靠性。在自愿放松测试中，30 和 60°/s 的 ROM 相对可靠性良好，尽管所有速度的 CVs 均≤10%，5°/s 时的测试则为中度可靠。当在 5°/s 下进行自愿肌肉活动时，测试才是可靠的，并且 ROM 可靠性为中度，CV≤8%。对于大多数变量，在慢速、放松测试和以更快速度或自愿激活进行的测试中，参与者的排名顺序不同，表明了不同的信息。在自愿放松的快速或主动伸展过程中，一个人的柔韧性状况往往与他们在传统的自愿放松、慢速测试中的状况不同。因此，“灵活性”测试应在不同的拉伸速度和肌肉力量产生水平下进行，临床医生和研究人员应考虑从较慢速度的自愿放松测试中得出的略微较大的日间变异性。
