The Effect of Personality Type on Muscle Coactivation during Elbow Flexion

摘要

A great deal of interest has been generated recently regarding the influence that psychosocial factors may have on the reporting of and disability associated with work-related musculoskeletal disorders. The current study considers the potential influence of one psychosocial factor -- personality type on basic neuromuscular control strategies and biomechanical loading. The study investigated the hypothe- sis that Type A people exhibit increased muscular antagonism relative to their Type B counter Parts. Volunteers participated in an EME-based biomechanical study to investigate the coactivation pattems of the major muscles that span the elbow joint during elbow flexion exertions. Results showed that, averaging across all conditions, the antagonist muscle activity was significantly higher for Type A individuals than for their Type B counterparts (l0/100 of maximum for Type. A, 5.5/100 of maximum for Type B). Although the study was somewhat limited in its size and scope, the results indicate that certain psychosocial factors may be more than a filter in postinjury response and may directly influence biomechanical loading. A potential application of this research is an increased awareness that certain individuals may be at greater risk of developing work-related musculo- skeletal disorders.