Abstract
Objective: The aim of this study was to investigate the effects of an EMG-based feedback device on the human musculoskeletal system by assessing the kinematics of the lumbar and cervical regions during computer operation. Methods: Using an EMG device, measurements were collected under four conditions: with feedback from the upper trapezius muscle, from the L4-erector spinae muscles and from both and without feedback (control). During periods of 15 min of computer operation, kinematic data were collected using the Zebris motion analysis system to investigate 14 university employees. Results: Feedback assessment effectively reduced the kinematic changes in the sagittal plane compared with the control (p<0.05). Feedback from the L4 erector spinae reduced the trunk flexion and forward head angles, which were significantly different compared with those under the feedback from the upper trapezius and the control conditions (p<0.05). Conclusion: We observed that the use of an EMG-based feedback device was effective in reducing habitual forward head and flexed-relaxed postures during computer operation. Additionally, posture correction from the lumbar region could be a way to reduce forward head posture as well as flexed-relaxed posture.
