Modulation of physiological cross-sectional area and fascicle length of vastus lateralis muscle in response to eccentric exercise.
Autor: | Marzilger R; Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Germany; Berlin School of Movement Science, Humboldt-Universität zu Berlin, Germany., Bohm S; Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Germany; Berlin School of Movement Science, Humboldt-Universität zu Berlin, Germany., Mersmann F; Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Germany; Berlin School of Movement Science, Humboldt-Universität zu Berlin, Germany., Arampatzis A; Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Germany; Berlin School of Movement Science, Humboldt-Universität zu Berlin, Germany. Electronic address: a.arampatzis@hu-berlin.de. |
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Jazyk: | angličtina |
Zdroj: | Journal of biomechanics [J Biomech] 2020 Oct 09; Vol. 111, pp. 110016. Date of Electronic Publication: 2020 Aug 28. |
DOI: | 10.1016/j.jbiomech.2020.110016 |
Abstrakt: | In the current study, we investigated the effect of lengthening velocity during eccentric exercise on the modulation of the physiological cross-sectional area (PCSA) and fascicle length of the vastus lateralis (VL) muscle. We hypothesized a greater increase in muscle PCSA after training with lower lengthening velocities and a greater increase in fascicle length after higher lengthening velocities. Forty-seven young men were randomly assigned to either a control (n = 14) or an intervention group (n = 33). The participants of the intervention group were randomly allocated to one of four isokinetic eccentric training protocols of the knee extensors, with four different knee angular velocities (45°/s, 120°/s, 210°/s and 300°/s), yet similar range of motion (25-100° knee joint angle), load magnitude (100% of isometric maximum) and load volume (i.e. similar time under tension for one training set). Before and after an 11-week training period with 3 times per week exercise, muscle volume, pennation angle, fascicle length and PCSA of the VL muscle were measured using magnetic resonance imaging and ultrasonography. After the training, the VL muscle volume and fascicle length increased similarly and approximately 5% in all investigated protocols. The PCSA and pennation angles of the VL did not change after any exercise protocol, indicating negligible radial muscle adaptation after the training. The reason for the found hypertrophy of VL muscle after eccentric training in a wide range of lengthening velocities was mainly a longitudinal muscle growth. Further, the longitudinal muscle growth was independent of the lengthening velocity. Competing Interests: Declaration of Competing Interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. (Copyright © 2020 Elsevier Ltd. All rights reserved.) |
Databáze: | MEDLINE |
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