Janshen Lars, Santuz Alessandro, Ekizos Antonis, Arampatzis Adamantios
Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Philippstraße 13, Haus 11, Berlin 10115, Germany.
Berlin School of Movement Science, Humboldt-Universität zu Berlin, Philippstraße 13, Haus 11, Berlin 10115, Germany.
J Exp Biol. 2017 Mar 1;220(Pt 5):807-813. doi: 10.1242/jeb.148957. Epub 2016 Dec 15.
The neuromuscular control of human movement can be described by a set of muscle synergies factorized from myoelectric signals. There is some evidence that the selection, activation and flexible combination of these basic activation patterns are of a neural origin. We investigated the muscle synergies during incline and level walking to evaluate changes in the modular organization of neuromuscular control related to changes in the mechanical demands. Our results revealed five fundamental (not further factorizable) synergies for both walking conditions but with different frequencies of appearance of the respective synergies during incline compared with level walking. Low similarities across conditions were observed in the timing of the activation patterns (motor primitives) and the weightings of the muscles within the respective elements (motor modules) for the synergies associated with the touchdown, mid-stance and early push-off phase. The changes in neuromuscular control could be attributed to changes in the mechanical demands in support, propulsion and medio-lateral stabilization of the body during incline compared with level walking. Our findings provide further evidence that the central nervous system flexibly uses a consistent set of neural control elements with a flexible temporal recruitment and modifications of the relative muscle weightings within each element to provide stable locomotion under varying mechanical demands during walking.
人类运动的神经肌肉控制可以通过从肌电信号中分解出的一组肌肉协同作用来描述。有证据表明，这些基本激活模式的选择、激活和灵活组合源于神经。我们研究了上坡行走和平地行走过程中的肌肉协同作用，以评估与机械需求变化相关的神经肌肉控制模块化组织的变化。我们的结果揭示了两种行走条件下的五种基本（不可进一步分解）协同作用，但与平地行走相比，上坡行走时各协同作用出现的频率不同。在与着地、支撑中期和早期蹬离阶段相关的协同作用中，观察到不同条件下激活模式（运动原基）的时间和各元素（运动模块）内肌肉的权重相似度较低。与平地行走相比，上坡行走时神经肌肉控制的变化可归因于身体在支撑、推进和内外侧稳定方面机械需求的变化。我们的研究结果进一步证明，中枢神经系统灵活地使用一组一致的神经控制元素，通过灵活的时间募集和改变每个元素内相对肌肉权重，在行走过程中不同的机械需求下提供稳定的运动。
