Avoiding Repetitive- Stress Injuries: A Guide for the Technical Communicator Article Written by Geoffrey J.S. Hart Presented By Alan Smith

Computers and Repetitive Stress Injuries  While computers are extremely helpful, they can also be hurtful.  A repetitive-stress injury, or RSI, is simply any injury that results from overuse of a body part without giving it time to recover.  W. Wayt Gibbs used the Mouse Odometer software ( and found that in a single 5- day period, he'd recorded 2440 feet of mouse movement and nearly mouse clicks!

The 3 Most Common RSIs with Computer Usage  Aches and Pains  Hand Problems  Eye Strain

Aches and Pains  The human body wasn't designed to sit still for hours at a time.  If you become a computer potato, you can expect your body to suffer.  “Spending your days hunch-backed over a computer, arms awkwardly extended, is a sure recipe for disaster.”

The Seat of the Problem  Sitting for hours compresses the tissues of your buttocks and upper thighs, thereby reducing blood flow to your legs.  Improperly positioned backs and seats on chairs can encourage a slumped posture that misaligns your spine and places additional stress on muscles, bones, and connective tissues  The seat and back cushions must comfortably distribute and support your weight.  This minimizes the pressure on any one part of your body.  Also, the back and armrests rest should be adjustable so they can cradle and support your back and arms.  Don't buy a cheap chair! Don’t skip the “test drive” etiher.

Maybe It’s The Mouse  A mouse typically lies on the right side of the keyboard.  That additional bit of stretching can create too much stress on the shoulder.  Try moving the mouse to the left of the keyboard.  This can dramatically reduce shoulder pain.  It can take only a week to master left-handed mousing.  Some users find that a "keyboard bridge“, or "mouse caddy", lets them keep mousing with their right hand.

Hand Problems  Carpal Tunnel Syndrome, or CTS, results from compression of the nerve that runs through the "carpal tunnel" in your wrist.  Over time, the abused nerve tissues swell, causing excruciating pain, loss of grip strength, and decreased ability to manipulate objects.  Many other problems of varying severity can mimic CTS.  Some problems may eventually go on to develop true CTS if they ignore their symptoms.  Your family doctor is a good place to start troubleshooting your body, but you may need to see a specialist.

The Key to the Hand Problem  Many hand problems, including CTS, arise from flexing your wrist too sharply outwards, with your little finger pointing further towards your elbow than it does at rest.  You can decrease your hand pain enormously by switching to Microsoft's Natural Keyboard.  This keyboard helps you keep your wrists straight while you type. More expensive ergonomic keyboards exist, and are worth investigating if you have or are developing serious hand problems.

Eye Strain  Human eyes aren't designed to stare at nearby objects at an unvarying distance for most of a day  Take frequent (hourly) breaks to gaze upon something more distant than your monitor.  Varying the sight distance exercises the muscles that help your eyes focus and stops those muscles from locking into painful rigidity.

Help Your Eyes Focus  Try placing your monitor at arm's length from your body.  Not so close that you bug out your eyes trying to see the whole picture, nor yet so far you must squint to see the text.  If you need eyeglasses, ask your optometrist about obtaining "computer glasses" designed specifically to help your eyes focus at the distance of your monitor.  Multifocal lenses help you focus comfortably at different distances by looking through different parts of the lens.  However, you may want to get glasses specifically designed for looking only at the screen -- just as many people have special "reading" glasses.

Improve the Lightning  Use lights that don’t flicker.  Traditional fluorescent lights flicker so badly that many people can see the flickering.  The flickering usually occurs at a different frequency from that of the monitor, and this difference can increase the perceived problem.  Use compact fluorescent lights because:  They flicker much less noticeably  They draw considerably less power and can shave your electrical bill enough to quickly repay their higher cost.  Traditional incandescent lights, though less energy-efficient, are also flicker-free.

Conclusion  Invest in good tools.  Stay in shape.  Let technology help.  Listen to your body. Questions?