Kawakami Y, Abe T, Kuno S Y, Fukunaga T
Department of Life Sciences, University of Tokyo, Japan.
Eur J Appl Physiol Occup Physiol. 1995;72(1-2):37-43. doi: 10.1007/BF00964112.
Five men underwent unilateral resistance training of elbow extensor (triceps brachii) muscles for 16 weeks. Before and after training, muscle layer thickness and fascicle angles of the long head of the triceps muscle were measured in vivo using B-mode ultrasound, and fascicle lengths were estimated. Series anatomical cross-sectional areas (ACSA) of the triceps brachii muscle were measured by magnetic resonance imaging, from which muscle volume (Vm) was determined and physiological cross-sectional area (PCSA) was calculated. Elbow extension strength (isometric; concentric and eccentric at 30, 90 and 180 degrees.s-1) was measured using an isokinetic dynamometer to determine specific tension. Muscle volumes, ACSA, PCSA, muscle layer thickness and fascicle angles increased after training and their relative changes were similar, while muscle and fascicle length did not change. Muscle strength increased at all velocities; however, specific tension decreased after training. Increase in fascicle angles, which would be the result of increased Vm and PCSA, would seem to imply the occurrence of changes in muscle architecture. This might have given a negative effect on the force-generating properties of the muscles.
五名男性接受了为期16周的单侧肘部伸肌（肱三头肌）抗阻训练。在训练前后，使用B超在体测量肱三头肌长头的肌层厚度和肌束角度，并估算肌束长度。通过磁共振成像测量肱三头肌的系列解剖横截面积（ACSA），由此确定肌肉体积（Vm）并计算生理横截面积（PCSA）。使用等速测力计测量肘部伸展力量（等长；在30、90和180度·秒-1时的向心和离心力量）以确定比张力。训练后肌肉体积、ACSA、PCSA、肌层厚度和肌束角度增加，且它们的相对变化相似，而肌肉和肌束长度未改变。在所有速度下肌肉力量均增加；然而，训练后比张力降低。肌束角度的增加似乎意味着肌肉结构发生了变化，这可能是Vm和PCSA增加的结果。这可能对肌肉的发力特性产生了负面影响。
