The computer is a vital tool in many different jobs and activities, for adults and children. But long periods of using a computer can increase your chance of developing an injury. Inappropriate computer use can cause muscle and joint pain, overuse injuries of the shoulder, arm, wrist or hand, and eyestrain.
Posture-related injuries from computer use
Back and neck pain, headaches, and shoulder and arm pain are common computer-related injuries. Such muscle and joint problems can be caused or made worse by poor workstation (desk) design, bad posture and sitting for long periods of time.
Although sitting requires less muscular effort than standing, it still causes physical fatigue (tiredness) and you need to hold parts of your body steady for long periods of time. This reduces circulation of blood to your muscles, bones, tendons and ligaments, sometimes leading to stiffness and pain. If a workstation is not set up properly, these steady positions can put even greater stress on your muscles and joints.
Preventing computer-related muscle and joint injuries
Tips to avoid muscle and joint problems include:
- Sit at an adjustable desk specially designed for use with computers.
- Have the computer monitor (screen) either at eye level or slightly lower.
- Have your keyboard at a height that lets your elbows rest comfortably at your sides. Your forearms should be roughly parallel with the floor and level with the keyboard.
- Adjust your chair so that your feet rest flat on the floor, or use a footstool.
- Use an ergonomic chair, specially designed to help your spine hold its natural curve while sitting.
- Use an ergonomic keyboard so that your hands and wrists are in a more natural position.
- Take frequent short breaks and go for a walk, or do stretching exercises at your desk. Stand often.
Computer-related overuse injuries of the hand or arm
Muscles and tendons can become painful with repetitive movements and awkward postures. This is known as ‘overuse injury’ and typically occurs in the elbow, wrist or hand of computer users. Symptoms of these overuse injuries include pain, swelling, stiffness of the joints, weakness and numbness.
Preventing computer-related overuse injuries
Tips to avoid overuse injuries of the hand or arm include:
- Have your mouse at the same height as your correctly positioned keyboard.
- Position the mouse as close as possible to the side of the keyboard.
- Use your whole arm, not just your wrist, when using the mouse.
- Type lightly and gently.
- Mix your tasks to avoid long, uninterrupted stretches of using the computer.
- Remove your hands from the keyboard when not actively typing, to let your arms relax.
Eyestrain from computer use
Focusing your eyes at the same distance point for long periods of time causes fatigue. The human eye structurally prefers to look at objects more than six metres away, so any work performed close up puts extra demands on your eye muscles. The illuminated computer screen can also cause eye fatigue. Although there is no evidence that eye fatigue damages your eyesight, computer users may get symptoms such as blurred vision, temporary inability to focus on faraway objects and headaches.
Preventing eyestrain from computer use
Tips to avoid eyestrain include:
- Make sure your main source of light (such as a window) is not shining into your face or directly onto the computer screen.
- Tilt the screen slightly to avoid reflections or glare.
- Make sure the screen is not too close to your face.
- Put the screen either at eye level or slightly lower.
- Reduce the contrast and brightness of your screen by adjusting the controls.
- Frequently look away from the screen and focus on faraway objects.
- Have regular eye examinations to check that any blurring, headaches and other associated problems are not caused by any underlying disorders.