Posture-movement changes following repetitive motion-induced shoulder muscle fatigue |
| |
| Authors: | Jason R. Fuller Karen V. Lomond Joyce Fung Julie N. Côté |
| |
| Affiliation: | 1. School and Graduate Institute of Physical Therapy, College of Medicine, National Taiwan University, Taipei, Taiwan, ROC;2. Department of Physical Medicine & Rehabilitation, Chang Gung Memorial Hospital at Linkou and College of Medicine, Chang Gung University, Taoyuan, Taiwan, ROC;3. Department of Biomedical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran;4. Department of Physical Therapy, College of Medicine, National Cheng Kung University, Taiwan, ROC;5. Graduate Institute of Biomedical Engineering, National Chung Hsing University, Taichung, Taiwan, ROC;6. School of Physical Therapy and Graduate Institute of Rehabilitation Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan, ROC;7. Bone and Joint Research Center, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan, ROC;8. Department of Orthopaedic Surgery, Chang Gung Memorial Hospital, Linkou, Taiwan, ROC |
| |
| Abstract: | Repetitive motion-induced fatigue not only alters local motion characteristics but also provokes global reorganization of movement. However, the three-dimensional (3D) characteristics of these reorganization patterns have never been documented in detail. The goal of this study was to assess the effects of repetitive reaching-induced arm fatigue on the whole-body, 3D biomechanical task characteristics. Healthy subjects (N = 14) stood and performed a continuous reaching task (RRT) between two targets placed at shoulder height to fatigue. Whole-body kinematic (Vicon©), kinetic (AMTI© force platforms) and electromyographic (EMG, Noraxon©) characteristics were recorded. Maximal voluntary isometric efforts (MVIE) of the shoulder and elbow were measured pre- and post-RRT. Post-RRT shoulder elevation MVIE was reduced by 4.9 ± 8.3% and trapezius EMG amplitude recorded during the RRT increased by 46.9 ± 49.9% from the first to last minute of the RRT, indicating that arm fatigue was effectively induced. During fatigued reaching, subjects elevated their shoulder (11.7 ± 10.5 mm) and decreased their average shoulder abduction angle by 8.3 ± 4.4°. These changes were accompanied by a lateral shift of the body’s center of mass towards the non-reaching arm. These findings suggest a compensatory strategy to decrease the load on the fatigued shoulder musculature. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
