Muscular sound and force relationship during isometric contraction in man
Muscular sound and force relationship during isometric contraction in man
复制标题
人体等长收缩时肌肉声音与力量的关系
DOI：
10.1007/bf02330708
复制
发表时间：
2006
期刊：
影响因子：
--
通讯作者：
A. Veicsteinas
中科院分区：
文献类型：
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作者：
C. Orizio;R. Perini;A. Veicsteinas
摘要收缩的肌肉产生一个低频的声音，在腹部表面可检测到，范围从11到40赫兹。为了研究肌肉声与收缩强度之间的关系，用接触式传感器记录了7名年轻健康男性肱二头肌的声音肌电（SMG），这些男性进行了4s等长收缩，从最大随意收缩（MVC）的10%到100%，以10%的步长。同时，记录肌电图（EMG）作为肌肉活动的指标。SMG和EMG通过常规方法（iSMG和iEMG）整合。iSMG和iEMG与MVC%之间的关系分别由高达80%和100%MVC的抛物线函数描述。超过80%MVC，iSMG降低，约为100%MVC时最大值的一半。我们的研究结果表明，运动单位募集和放电率以相同的方式影响iSMG和iEMG高达80%MVC。从80%到100%MVC，高运动单元的放电率和肌肉刚度一起限制了由活性纤维的尺寸变化产生的压力波。肌肉声似乎反映了肌肉内的粘弹性特征和收缩肌肉的运动单元激活模式。
SummaryThe contracting muscle generates a low frequency sound detectable at the belly surface, ranging from 11 to 40 Hz. To study the relationship between the muscular sound and the intensity of the contraction a sound myogram (SMG) was recorded by a contact sensor from the biceps brachii of seven young healthy males performing 4-s isometric contractions from 10% to 100% of the maximal voluntary contraction (MVC), in 10% steps. Simultaneously, the electromyogram (EMG) was recorded as an index of muscle activity. SMG and EMG were integrated by conventional methods (iSMG and iEMG). The relationship between iSMG and iEMG vs MVC% is described by parabolic functions up to 80% and 100% MVC respectively. Beyond 80% MVC the iSMG decreases, being about half of its maximal value at 100% MVC. Our results indicate that the motor unit recruitment and firing rate affect the iSMG and iEMG in the same way up to 80% MVC. From 80% to 100% MVC the high motor units' discharge rate and the muscular stiffness together limit the pressure waves generated by the dimensional changes of the active fibres. The muscular sound seems to reflect the intramuscular visco-elastic characteristics and the motor unit activation pattern of a contracting muscle.