caa a22 4500 469054662 CHVBK 20180323132840.0 cr unu---uuuuu 170328e19921101xx s 000 0 eng 10.1007/BF00243511 doi (NATIONALLICENCE)springer-10.1007/BF00243511 Assessment of human knee extensor muscles stress from in vivo physiological cross-sectional area and strength measurements [Elektronische Daten] [M. Narici, L. Landoni, A. Minetti] Summary: 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 (F t) 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 (F f) of each muscle, F t was divided by the cosine of the angle of pennation and multiplied for (CSAp · ΣCSAp−1), where ΣCSAp was the sum of CSAp of the four muscles. The resulting F f 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 × 10−3 (SD 2.54 × 10−3) m2 for VL, 8.35 × 10−3 (SD 1.17 × 10−3) m2 for VI, 6.80 × 10−3 (SD 2.66 × 10−3) m2 for VM and 6.62 × 10−3 (SD 1.21 × 10−3) m2 for RE The mean value of stress of VL, VI, VM and RF was 250 (SD 19) kN m2; this value is in good agreement with data on animal muscle and those on human parallel-fibred muscle. Springer-Verlag, 1992 Force/CSA nationallicence Muscle stress nationallicence Specific tension nationallicence Skeletal muscle strength nationallicence MRI nationallicence Narici M. Reparto Fisiologia Lavoro Muscolare, Istituto di Tecnologie Biomediche Avanzate, Consiglio Nazionale delle Ricerche, Via Ampère 56, I-20131, Milan, Italy aut Landoni L. Centro S. Pio X, Servizio di Risonanza Magnetica, Via Nava 31, I-20159, Milan, Italy aut Minetti A. Reparto Fisiologia Lavoro Muscolare, Istituto di Tecnologie Biomediche Avanzate, Consiglio Nazionale delle Ricerche, Via Ampère 56, I-20131, Milan, Italy aut European Journal of Applied Physiology and Occupational Physiology Springer-Verlag 65/5(1992-11-01), 438-444 0301-5548 65:5<438 1992 65 421 https://doi.org/10.1007/BF00243511 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00243511 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Narici M. Reparto Fisiologia Lavoro Muscolare, Istituto di Tecnologie Biomediche Avanzate, Consiglio Nazionale delle Ricerche, Via Ampère 56, I-20131, Milan, Italy aut NATIONALLICENCE 700 1- Landoni L. Centro S. Pio X, Servizio di Risonanza Magnetica, Via Nava 31, I-20159, Milan, Italy aut NATIONALLICENCE 700 1- Minetti A. Reparto Fisiologia Lavoro Muscolare, Istituto di Tecnologie Biomediche Avanzate, Consiglio Nazionale delle Ricerche, Via Ampère 56, I-20131, Milan, Italy aut NATIONALLICENCE 773 0- European Journal of Applied Physiology and Occupational Physiology Springer-Verlag 65/5(1992-11-01), 438-444 0301-5548 65:5<438 1992 65 421 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer