Effects of different working postures and pointing devices on energy expenditure, upper limb and back muscles activity, task performance and perception

This study simultaneously compared four working postures (sitting on an office chair, on a ball, standing and pedalling on an ergocycle) and five pointing device configurations (traditional and slanted mouse placed next to and in front of the keyboard, and central pointing device) in relation to sedentary behaviour and musculoskeletal disorders. Pedalling on an ergocycle was the only posture that exceeded the sedentary behaviour threshold of 1.5 METs. This posture resulted in the highest task completion time and was least favoured by participants. Regardless of the pointing device configuration, there was a risk of fatigue in the extensor carpi muscle of the dominant limb. Nevertheless, the central pointing device reduced stress on this muscle compared to mice. Task performance was the best with the traditional mouse. Using the central pointing device while pedalling on an ergocycle led to the lowest task performance and the highest stress on the trapezius muscle. Compared to standing and sitting on a chair or a ball, using an ergocycle was the only posture reaching a sufficient energy expenditure with respect to sedentary behaviour. Traditional and slanted mice and central pointing device entail a risk of muscular fatigue. However, it was less with central pointing device.