Bülow P M, Nørregaard J, Danneskiold-Samsøe B, Mehlsen J
Department C, Frederiksberg Hospital, Denmark.
Eur J Appl Physiol Occup Physiol. 1993;67(5):462-6. doi: 10.1007/BF00376464.
The aim was to study the methodological aspects of the muscle twitch interpolation technique in estimating the maximal force of contraction in the quadriceps muscle utilizing commercial muscle testing equipment. Six healthy subjects participated in seven sets of experiments testing the effects on twitch size of potentiation, time lag after potentiation, magnitude of voluntary force, stimulus amplitude, stimulus duration, angle of the knee, and angle of the hip. In addition, the consequences of submaximal potentiation on the estimation of maximal force from twitch sizes were studied in five healthy subjects. We found an increase in twitch size with increasing levels of potentiation and twitch size decreased exponentially following potentiation. We found a curvilinear relationship between twitch size and voluntary force, and these properties were more obvious when the stimulation intensity of the preload was reduced. The relationship between twitch size and force was only linear, for force levels greater than 25% of maximum. It was concluded that to achieve an accurate estimate of true maximal force of muscle contraction, it would be necessary for the subject to be able to perform at least 75% of the true maximal force.
目的是利用商用肌肉测试设备，研究肌肉抽搐插值技术在估计股四头肌最大收缩力方面的方法学问题。六名健康受试者参与了七组实验，测试增强作用对抽搐大小的影响、增强作用后的时间延迟、随意力大小、刺激幅度、刺激持续时间、膝关节角度和髋关节角度。此外，还在五名健康受试者中研究了次最大增强作用对根据抽搐大小估计最大力的影响。我们发现，随着增强水平的增加，抽搐大小增加，增强作用后抽搐大小呈指数下降。我们发现抽搐大小与随意力之间存在曲线关系，当预负荷的刺激强度降低时，这些特性更为明显。对于大于最大力25%的力水平，抽搐大小与力之间仅呈线性关系。得出的结论是，为了准确估计肌肉收缩的真正最大力，受试者必须能够至少发挥真正最大力的75%。
