Fabre-Adinolfi Dimitri, Parietti-Winkler Cécile, Pierret Jonathan, Lassalle-Kinic Benoîte, Frère Julien
Université de Lorraine, Laboratory « Développement, Adaptation et Handicap » (EA 3450), F-54000 Nancy, France; University Hospital of Nancy, Department of Oto-Rhino-Laryngology Head and Neck Surgery, F-54000 Nancy, France.
Université de Lorraine, Laboratory « Développement, Adaptation et Handicap » (EA 3450), F-54000 Nancy, France; L.-Pierquin Rehabilitation Center, F-54000 Nancy, France.
Hum Mov Sci. 2018 Dec;62:150-160. doi: 10.1016/j.humov.2018.10.010. Epub 2018 Oct 26.
It has been suggested that vestibular cues are inhibited for the benefit of spinal locomotor centres in parallel with the increase in locomotion speed. This study aimed at quantifying the influence of a transient vestibular tone imbalance (TVTI) on gait kinematics, muscle activity and muscle synergies during walking and running. Twelve participants walk or run at a self-selected speed with or without TVTI, which was generated by 10 body rotations just prior the locomotion task. Three-dimensional lower-limb kinematic was recorded simultaneously with the surface electromyographic (EMG) activity of 8 muscles to extract muscle synergies via non-negative matrix factorization. Under TVTI, there was an increased gait deviation in walking compared to running (22.8 ± 8.4° and 8.5 ± 3.6°, respectively; p < 0.01), while the number (n = 4) and the composition of the muscle synergies did not differ across conditions (p = 0.78). A higher increase (p < 0.05) in EMG activity due to TVTI was found during walking compared to running, especially during stance. These findings confirmed that the central nervous system inhibited misleading vestibular signals according to the increase in locomotion speed for the benefit of spinal mechanisms, expressed by the muscle synergies.
有人提出，随着运动速度的增加，前庭线索会受到抑制，以利于脊髓运动中枢。本研究旨在量化短暂前庭张力失衡（TVTI）对步行和跑步过程中步态运动学、肌肉活动和肌肉协同作用的影响。12名参与者在有或没有TVTI的情况下以自选速度行走或跑步，TVTI是在运动任务开始前通过10次身体旋转产生的。同时记录三维下肢运动学和8块肌肉的表面肌电图（EMG）活动，通过非负矩阵分解提取肌肉协同作用。在TVTI情况下，与跑步相比，步行时的步态偏差增加（分别为22.8±8.4°和8.5±3.6°；p<0.01），而肌肉协同作用的数量（n=4）和组成在不同条件下没有差异（p=0.78）。与跑步相比，步行时因TVTI导致的EMG活动增加幅度更大（p<0.05），尤其是在站立期。这些发现证实，中枢神经系统根据运动速度的增加抑制误导性的前庭信号，以利于由肌肉协同作用所体现的脊髓机制。
