Baur Heiner, Groppa Alessia Severina, Limacher Regula, Radlinger Lorenz
Bern University of Applied Sciences, Health, Physiotherapy, Bern, Switzerland.
J Sport Rehabil. 2016 Feb 2;25(1). doi: 10.1123/jsr.2014-0241. Print 2016 Feb 1.
Maximum strength and rate of force development (RFD) are 2 important strength characteristics for everyday tasks and athletic performance. Measurements of both parameters must be reliable. Expensive isokinetic devices with isometric modes are often used. The possibility of cost-effective measurements in a practical setting would facilitate quality control. The purpose of this study was to assess the reliability of measurements of maximum isometric strength (Fmax) and RFD on a conventional leg press. Sixteen subjects (23 ± 2 y, 1.68 ± 0.05 m, 59 ± 5 kg) were tested twice within 1 session. After warm-up, subjects performed 2 times 5 trials eliciting maximum voluntary isometric contractions on an instrumented leg press (1- and 2-legged randomized). Fmax (N) and RFD (N/s) were extracted from force-time curves. Reliability was determined for Fmax and RFD by calculating the intraclass correlation coefficient (ICC), the test-retest variability (TRV), and the bias and limits of agreement. Reliability measures revealed good to excellent ICCs of .80-.93. TRV showed mean differences between measurement sessions of 0.4-6.9%. The systematic error was low compared with the absolute mean values (Fmax 5-6%, RFD 1-4%). The implementation of a force transducer into a conventional leg press provides a viable procedure to assess Fmax and RFD. Both performance parameters can be assessed with good to excellent reliability allowing quality control of interventions.
最大力量和力量发展速率（RFD）是日常活动和运动表现的两个重要力量特征。这两个参数的测量必须可靠。常使用带有等长模式的昂贵等速设备。在实际环境中进行具有成本效益的测量的可能性将有助于质量控制。本研究的目的是评估在传统腿举机上测量最大等长力量（Fmax）和RFD的可靠性。16名受试者（23±2岁，身高1.68±0.05米，体重59±5千克）在一次测试中接受了两次测试。热身之后，受试者在一台装有仪器的腿举机上进行2组，每组5次最大自主等长收缩试验（单腿和双腿随机）。从力-时间曲线中提取Fmax（牛顿）和RFD（牛顿/秒）。通过计算组内相关系数（ICC）、重测变异性（TRV）以及偏差和一致性界限来确定Fmax和RFD的可靠性。可靠性测量结果显示ICC为0.80 - 0.93，表现良好至优秀。TRV显示测量时段之间的平均差异为0.4 - 6.9%。与绝对平均值相比，系统误差较低（Fmax为5 - 6%，RFD为1 - 4%）。在传统腿举机中安装力传感器为评估Fmax和RFD提供了一种可行的方法。两个性能参数都可以以良好至优秀的可靠性进行评估，从而实现对干预措施的质量控制。
