Differential activation of the plantar flexor muscles in balance control across different feet orientations on the ground |
| |
| Institution: | 1. Human Motor Systems Laboratory, School of Physical Education and Sport, University of São Paulo, Av. Professor Mello Moraes, 65, Butantã, São Paulo 05508-030, Brazil;2. Biomedical Engineering, Federal University of ABC, Av. da Universidade, Anchieta, São Bernardo do Campo, São Paulo 09606-045, Brazil;1. Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Rochester, MN, United States;2. Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, United States;3. Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN, United States;1. University of Southern California, United States;2. Rancho Los Amigos National Rehabilitation Center, United States;1. Programa de Engenharia Biomédica (COPPE), Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil;2. Centre of Precision Rehabilitation for Spinal Pain (CPR Spine), School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, UK;3. Department of Clinical and Experimental Sciences, Università degli Studi di Brescia, Brescia, Italy;4. Laboratorio di Ingegneria del Sistema Neuromuscolare (LISiN), Politecnico di Torino, Torino, TO, Italy;5. PolitoBIOMed Lab, Politecnico di Torino, Torino, Italy;1. School of Electrical & Electronic Engineering, University College Dublin, Dublin, Ireland;2. School of Public Health, Physiotherapy and Sports Science, University College Dublin, Dublin, Ireland;3. Biomedical Sciences Department, Neuromuscular Physiology Laboratory, University of Padova, Italy |
| |
| Abstract: | The ankle plantar flexor muscles act synergistically to control quiet and dynamic body balance. Previous research has shown that the medial (MG) and lateral (LG) gastrocnemii, and soleus (SOL) are differentially activated as a function of motor task requirements. In the present investigation, we evaluated modulation of the plantar flexors' activation from feet orientation on the ground in an upright stance and the ensuing reactive response to a perturbation. A single group of young participants (n = 24) was evaluated in a task requiring initial stabilization of body balance against a backward pulling load (5% or 10% of body weight) attached to their trunk, and then the balance was suddenly perturbed, releasing the load. Four feet orientations were compared: parallel (0°), outward orientation at 15° and 30°, and the preferred orientation (M = 10.5°). Results revealed a higher activation magnitude of SOL compared to MG-LG when sustaining quiet balance against the 10% load. In the generation of reactive responses, MG was characterized by earlier, steeper, and proportionally higher activation than LG-SOL. Feet orientation at 30° led to higher muscular activation than the other orientations, while the activation relationship across muscles was unaffected by feet orientation. Our results support the conclusion of task-specific differential modulation of the plantar flexor muscles for balance control. |
| |
| Keywords: | Triceps surae Differential muscle activation Automatic postural response Feet positioning |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
