Narici M V, Landoni L, Minetti A E
Reparto Fisiologia Lavoro Muscolare, Istituto di Tecnologie Biomediche Avanzate, Milan, Italy.
Eur J Appl Physiol Occup Physiol. 1992;65(5):438-44. doi: 10.1007/BF00243511.
The physiological cross-sectional areas (CSAp) of the vastus lateralis (VL), vastus intermedius (VI), vastus medialis (VM) and rectus femoris (RF) were obtained, in vivo, from the reconstructed muscle volumes, angles of pennation and distance between tendons of six healthy male volunteers by nuclear magnetic resonance imaging (MRI). In all subjects, the isometric maximum voluntary contraction strength (MVC) was measured at the optimum angle at which peak force occurred. The MVC developed at the ankle was 746.0 (SD 141.8) N and its tendon component (Ft), given by a mechanical advantage of 0.117 (SD 0.010), was 6.367 (SD 1.113) kN. To calculate the force acting along the fibres (Ff) of each muscle, Ft was divided by the cosine of the angle of pennation and multiplied for (CSAp.sigma CSAp-1), where sigma CSAp was the sum of CSAp of the four muscles. The resulting Ff values of VL, VI, VM and RF were: 1.452 (SD 0.531) kN, 1.997 (SD 0.187) kN, 1.914 (SD 0.827) kN, and 1.601 (SD 0.306) kN, respectively. The stress of each muscle was obtained by dividing these forces for the respective CSAp which was: 6.24 x 10(-3) (SD 2.54 x 10(-3)) m2 for VL, 8.35 x 10(-3) (SD 1.17 x 10(-3)) m2 for VI, 6.80 x 10(-3) (SD 2.66 x 10(-3)) m2 for VM and 6.62 x 10(-3) (SD 1.21 x 10(-3)) m2 for RF. The mean value of stress of VL, VI, VM and RF was 250 (SD 19) kN m-2; this value is in good agreement with data on animal muscle and those on human parallel-fibred muscle.
通过核磁共振成像（MRI），从六名健康男性志愿者的重建肌肉体积、羽状角和肌腱间距中，在活体状态下获取了股外侧肌（VL）、股中间肌（VI）、股内侧肌（VM）和股直肌（RF）的生理横截面积（CSAp）。在所有受试者中，在产生峰值力的最佳角度测量等长最大自主收缩力量（MVC）。在脚踝处产生的MVC为746.0（标准差141.8）N，其肌腱成分（Ft），机械优势为0.117（标准差0.010），为6.367（标准差1.113）kN。为了计算作用于每块肌肉纤维（Ff）上的力，Ft除以羽状角的余弦值，并乘以（CSAp·∑CSAp -1），其中∑CSAp是四块肌肉的CSAp之和。VL、VI、VM和RF的所得Ff值分别为：1.452（标准差0.531）kN、1.997（标准差0.187）kN、1.914（标准差0.827）kN和1.601（标准差0.306）kN。每块肌肉的应力通过将这些力除以各自的CSAp得到，VL的CSAp为：6.24×10⁻³（标准差2.54×10⁻³）m²，VI为8.35×10⁻³（标准差1.17×10⁻³）m²，VM为6.80×10⁻³（标准差2.66×10⁻³）m²，RF为6.62×10⁻³（标准差1.21×10⁻³）m²。VL、VI、VM和RF的平均应力值为250（标准差19）kN m⁻²；该值与动物肌肉数据和人类平行纤维肌肉数据高度一致。
