Computer mouse position as a determinant of posture, muscular load and perceived exertion

Area of Science:

• Ergonomics
• Human-Computer Interaction
• Occupational Health

Background:

• Computer mouse placement significantly impacts user posture and physical strain.
• Understanding biomechanical load is crucial for preventing work-related musculoskeletal disorders.

Purpose of the Study:

• To investigate the effects of six computer mouse positions on posture, muscular load, and perceived exertion during text editing.
• To identify optimal mouse placements for reducing physical strain in video display unit users.

Main Methods:

• Utilized an optoelectronic 3D motion analysis system to record postures.
• Measured muscular load using electromyography (EMG).
• Assessed perceived exertion via rating scales in 20 participants (10 men, 10 women).

Main Results:

• A neutral, relaxed arm posture with arm support demonstrated the lowest perceived exertion and trapezius muscle activity.
• Shorter operators exhibited higher muscle activity compared to taller operators, potentially due to anthropometric differences.
• Narrow-shouldered and short operators experienced greater shoulder abduction and external rotation when the mouse was positioned laterally to the keyboard.
• Arm support significantly reduced neck and shoulder muscle load.

Conclusions:

• Users preferred mouse positions allowing a near-neutral, relaxed arm posture with arm support.
• Mouse placement lateral to the keyboard created more strenuous arm postures for short and narrow-shouldered individuals.
• Optimizing mouse position and utilizing arm support are recommended for reducing physical strain during computer work.