Effects of notebook computer workstation settings on muscle activities and postural risks

Thirty-five healthy notebook computer (NBC) users were asked to operate a notebook computer for 1 hour at 3 workstation settings, namely, common NBC setting, desktop-style setting, and slant NBC setting. The activities of cervical paravertebral, upper trapezius, deltoids, and lumbar paravertebral muscles were recorded and analyzed, and the postural risk was assessed. It is found that the common NBC setting induced more muscle activity than the others. The Rapid Upper Limb Assessment (RULA) grand scores of the work posture at the common NBC workstation also significantly differ from those at the desktop-style and slant NBC workstations (p < 0.001). The results confirm that the desktop-style and slant NBC settings are recommended for NBC operations since they require lower muscle activities and impose lower postural risk.