Part two of a two-part article by Kathleen Hogan on the proper position for ergonomic computer use. (See Part 1)
In recent years, ergonomists have attempted to define postures that minimize unnecessary static work and reduce the detrimental forces acting on the body. All of us could significantly reduce our risk of injury if we followed these ergonomic principles:
- All work activities should permit us to adopt several different, but equally healthy and safe postures. It is important to adopt a proper position in front of a computer.
- Where muscular force has to be exerted it should be done by the largest appropriate muscle groups available. For example, when you lift a heavy box, you should bend your hips and knees and use your leg muscles to lift, not your back muscles. You should carry the load as close to, and as high on, your body as you can.
- Work activities should be performed with the joints at about mid-point of their range of movement. This applies particularly to the head, trunk, and upper limbs. (from www.ergonomics.org).
Here is an example of proper position in front of a computer and ergonomically correct furniture:
- The angle of the hips, knees, and elbows is approximately 90 degrees.
- The eyes gaze straight ahead, or slightly down.
- The seat is the correct depth so that the back is supported with the natural in and out curves allowed.
- The feet are flat on the floor ( or in this case the small footrest.), removing the strain on the low back.
- The wrists are supported with a pad.
- The mouse is neither too close nor too far away so that the shoulders are not strained.
What does this example have to do with using a lap desk? The two situations have several things in common:
- A lap desk allows you to maintain the natural curves of your spine.
- Because the surface is raised, you do not have to lean, twist or collapse into a bow to reach your lap and work.
- You can scoot to the back of the couch or bed and support your low back with appropriate cushioning.
- Your gaze is higher than it would be if your work was on your lap, so your neck stays in better alignment and you can tuck your chin. Jutting your chin out and collapsing your spine into a long “C” curve is a sure road to back and neck pain.
- You can relax your arms and shoulders because the desk will hold your work.
Remember that the cumulative effects of constant or repeated small stresses over a long period of time gives rise to the same kind of difficulties as a sudden severe stress. Keep yourself stretched out, allow yourself to move into a variety of positions and postures as you move and sit.
Keep your muscles strong by dancing, bike-riding, swimming, lifting weights, walking, etc. Use furniture that gives you the correct support. And use a lap desk whenever you work, play or eat on your lap!
Back to Part 1 of Computer Ergonomics and the Use of Lap Desks