Voluntary control of forward leaning posture relates to low-frequency neural inputs to the medial gastrocnemius muscle |
| |
| Institution: | 1. Department of Physical Therapy, Nagoya University Graduate School of Medicine, Nagoya, Aichi, 461-8673, Japan;2. Japan Society for the Promotion of Science, Tokyo, Japan;3. Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA;4. Department of Physical Therapy, University of Florida, Gainesville, FL, USA;1. Willy Taillard Laboratory of Kinesiology, Geneva University Hospitals and Geneva University, Switzerland;2. Univ Lyon, Université Lyon 1, IFSTTAR, LBMC UMR_T9406, F69622, Lyon, France;3. Pediatric Orthopaedic Service, Department of Child and Adolescent, Geneva University Hospitals and Geneva University, Geneva, Switzerland;1. Amsterdam Rehabilitation Research Center, Reade, Dr. Jan van Breemenstraat 2, PO 58271, 1040 HG, Amsterdam, the Netherlands;2. VU University Medical Center, Department of Rehabilitation Medicine, PO 7057, 1007 MB, Amsterdam, the Netherlands;3. Amsterdam Public Health research institute, VU University Medical Center, Van der Boechorststraat 7, 1081 BT, Amsterdam, the Netherlands;4. Department of Epidemiology and Biostatistics, VU University Medical Center, De Boelelaan 1089a, 1081 HV Amsterdam, the Netherlands;1. Department of System Design Engineering, Faculty of Science and Technology, Keio University, Yokohama, Japan;2. Department of Physical Therapy, Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan;3. Japan Society for the Promotion of Science, Tokyo, Japan;4. School of Science for Open and Environmental Systems, Graduate School of Science and Technology, Keio University, Yokohama, Japan;1. Institute for Biomechanics, ETH Zürich, Switzerland;2. Zurich Bone and Joint Institute, Switzerland;3. Schulthess Klinik Zürich, Switzerland;1. Univeristy of Southern California, Los Angeles, California, United States;2. Children’s Hospital Los Angeles, Los Angeles, California, United States |
| |
| Abstract: | BackgroundVariability is an inherent feature of the motor output. Although low-frequency oscillations (<0.5 Hz) are the most important contributor to the variability of force during single-joint isolated force tasks, it remains unclear whether they contribute to the variability of a more complex task, such as a voluntary postural task.Research questionDo low-frequency oscillations contribute to postural sway (center of pressure (COP) variability) when participants attempt to voluntarily maintain posture in a forward leaning position?MethodsFourteen healthy young adults performed two tasks: 1) stand quietly (control condition); 2) leaned their body forward to 60% of their maximum lean distance by dorsiflexing the ankle joint. We recorded the COP and electromyographic (EMG) activity from the medial gastrocnemius (MG) and soleus (SL) muscles. We quantified the following: 1) COP variability as the standard deviation (SD) of anteroposterior COP displacements; 2) modulation of COP as the power in COP displacements from 0 to 2 Hz; 3) modulation of EMG bursting as the power in the rectified and smoothed EMG from 0 to 2 Hz; 4) modulation of the interference EMG as the power in the EMG from 10 to 35 and 35–60 Hz.ResultsThe SD of COP displacements related to the COP oscillations <0.5 Hz in both quiet standing and lean tasks. However, only for the lean task, the <0.5 Hz COP oscillations related to the EMG burst oscillations <0.5 Hz of the MG muscle. The EMG burst oscillations <0.5 Hz of the MG muscle further related to the interference EMG oscillations from 35 to 60 Hz for the lean task.SignificanceVoluntary control of forward leaning posture relates to low-frequency neural inputs to the MG muscle. |
| |
| Keywords: | Variability Low-frequency oscillations Center of pressure Electromyogram |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
