Lower local dynamic stability and invariable orbital stability in the activation of muscle synergies in response to accelerated walking speeds

Benio Kibushi, Shota Hagio, Toshio Moritani, Motoki Kouzaki

研究成果: Article

抄録

In order to achieve flexible and smooth walking, we must accomplish subtasks (e. g., loading response, forward propulsion or swing initiation) within a gait cycle. To evaluate subtasks within a gait cycle, the analysis of muscle synergies may be effective. In the case of walking, extracted sets of muscle synergies characterize muscle patterns that relate to the subtasks within a gait cycle. Although previous studies have reported that the muscle synergies of individuals with disorders reflect impairments, a way to investigate the instability in the activations of muscle synergies themselves has not been proposed. Thus, we investigated the local dynamic stability and orbital stability of activations of muscle synergies across various walking speeds using maximum Lyapunov exponents and maximum Floquet multipliers. We revealed that the local dynamic stability in the activations decreased with accelerated walking speeds. Contrary to the local dynamic stability, the orbital stability of the activations was almost constant across walking speeds. In addition, the increasing rates of maximum Lyapunov exponents were different among the muscle synergies. Therefore, the local dynamic stability in the activations might depend on the requirement of motor output related to the subtasks within a gait cycle. We concluded that the local dynamic stability in the activation of muscle synergies decrease as walking speed accelerates. On the other hand, the orbital stability is sustained across broad walking speeds.

元の言語English
記事番号485
ジャーナルFrontiers in Human Neuroscience
12
DOI
出版物ステータスPublished - 2018 12 11
外部発表Yes

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Muscles
Gait
Walking
Walking Speed

ASJC Scopus subject areas

  • Neuropsychology and Physiological Psychology
  • Neurology
  • Psychiatry and Mental health
  • Biological Psychiatry
  • Behavioral Neuroscience

これを引用

Lower local dynamic stability and invariable orbital stability in the activation of muscle synergies in response to accelerated walking speeds. / Kibushi, Benio; Hagio, Shota; Moritani, Toshio; Kouzaki, Motoki.

:: Frontiers in Human Neuroscience, 巻 12, 485, 11.12.2018.

研究成果: Article

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