Task-induced electromyographic activation in fibromyalgia subjects and controls.

Ten female fibromyalgia subjects (mean age = 48.4) and ten matched healthy controls (mean age = 50.6) performed a perceptual-motor video task. Surface electromyography (EMG) was recorded from three sites before, during, and after perceptual-motor task performance (active and 'passive' forearms: Surface above m. flexor carpi radialis; neck: Surface above m. trapezius, right side). Task performance provoked EMG activation at all recording sites and in both subject groups, and scores failed to distinguish between the groups. However, the quality of task performance was inferior in the fibromyalgia group. Responses to motivational state measures obtained from the experimental situation revealed no group differences. The fibromyalgia subjects reported relatively high exposure to stressors attributed to their own body (but not to work, family, and economy), and high efforts invested to cope with such stressors in everyday life. The results failed to support a role for high muscle tension and anxiety in fibromyalgia.