Sitting or Standing for Computer Work — Does a Negative-Tilt Keyboard Tray Make a Difference?

Abstract

The effects of using an electric height-adjustable worksurface, with and without the addition of a negative-tilt keyboard tray, on wrist posture, comfort, typing performance and body movements was studied. Eighteen subjects experienced four test conditions: typing while sitting with the keyboard on a flat surface or negative tilt keyboard tray, and standing with the keyboard on a flat surface or negative tilt keyboard tray. Results show that the most neutral typing wrist posture (least wrist extension) was maintained when sitting rather than standing. There was a slight wrist posture benefit with the negative tilt tray for both sitting and standing. Sitting with a negative-tilt tray was the most comfortable condition. Sitting was more comfortable than standing. No performance differences between conditions were found. When sitting there was more foot movement than when standing. When standing there was more weight shifting than when sitting.