Force and surface mechanomyogram frequency responses in cat gastrocnemius.
Force and surface mechanomyogram frequency responses in cat gastrocnemius.
复制标题
猫腓肠肌的力和表面肌力图频率响应。
DOI：
10.1016/s0021-9290(99)00185-2
复制
发表时间：
2000
影响因子：
2.4
通讯作者：
A. Veicsteinas
中科院分区：
文献类型：
--
作者：
C. Orizio;R. Baratta;B. Zhou;M. Solomonow;A. Veicsteinas
肌肉表面位移是与肌腱产生张力同时发生的机械事件。这两种现象可以通过表面肌力图信号 (MMG)（由激光距离传感器产生）和力信号（来自称重传感器）来研究。本文的目的是为肌肉力学研究中激光检测 MMG 的可靠性提供数据。为此目的，验证了激光检测到的MMG是否适合估计猫内侧腓肠肌的频率响应，并将其频率响应与肌腱水平处的力信号检索到的频率响应进行比较。对四只猫暴露的腓肠肌内侧的力和 MMG 进行了分析。在不同的试验中，通过在 0.4-6Hz 范围内正弦改变有序募集的运动单位的数量来研究频率响应。结果是可以通过具有两个真实双极点和纯时间延迟的临界阻尼二阶系统对力和 MMG 频率响应进行建模。平均而言，力和 MMG 的极点分别为 1.83Hz（延迟 22.6ms）和 2.75Hz（延迟 38ms）。可以得出结论，MMG 似乎是研究刺激等长收缩期间肌肉频率响应的可靠工具。尽管在统计上不显着，但二阶系统参数的差异表明肌肉力学模型的不同组成部分可能会具体影响力或 MMG。
Muscle surface displacement is a mechanical event taking place simultaneously with the tension generation at the tendon. The two phenomena can be studied by the surface mechanomyogram signal (MMG) (produced by a laser distance sensor) and the force signal (from a load cell). The aim of this paper was to provide data on the reliability of the laser detected MMG in muscle mechanics research. To this purpose it was verified if the laser detected MMG was suitable to estimate a frequency response in the cat medial gastrocnemius and its frequency response was compared with the one retrieved by the force signal at the tendon level. The force and MMG from the exposed medial gastrocnemius of four cats were analysed. The frequency response was investigated by sinusoidally changing the number of orderly recruited motor units, in different trials, in the 0.4–6Hz range. It resulted that it was possible to model the force and MMG frequency response by a critically damped second-order system with two real double poles and a pure time delay. On the average, the poles were at 1.83Hz (with 22.6ms delay) and at 2.75Hz (with 38ms delay) for force and MMG, respectively. It can be concluded that MMG appears to be a reliable tool to investigate the muscle frequency response during stimulated isometric contraction. Even though not statistically significant, the differences in the second-order system parameters suggest that different components of the muscle mechanical model may specifically affect the force or MMG.