When setting up a computer workstation, especially at home, we tend to use whatever furniture we have handy. But "making do" may cost you more than it saves in the long run, due to decreased productivity and increased medical expenses. The more time you spend in front of the computer, the more important it is to adjust your workstation. Ideally, it should fit like custom-made clothing.

If you come away from a session at your computer with aching hands or eyes that feel full of sand, you may shrug off your discomforts as an unavoidable consequence of too much time at the keyboard. But the real problem probably isn't the quantity of time you spend at the computer. It's more likely caused by your physical positioning at the computer. Here are some tips on how to arrange yourself and your computing environment for optimum health and comfort.

A Desk That Fits

Physical proportions vary widely among individuals, yet we sit at mass-produced, one-size-fits-all desks. And like automobile seat belts, desks seem to be designed using a man as a model; they're usually too big for women.

Working at a desk that's too high off the floor can lead to all sorts of aches and pains, especially in your shoulders and neck. It can also trigger early fatigue and interfere with your ability to concentrate. A desk that's too low can also have physical repercussions, including an aching neck and upper back.

If resting your forearms on your desk causes your shoulders to rise upward, the desk is probably too tall. If your knees continually bump against the underside, even when your feet are flat on the floor, it's probably too short.

To elevate a desk that's too low, place boards or other stable and sturdy braces beneath the legs. Lowering a desk is a bit trickier. One rather permanent method is to use a saw to trim an inch or two from the legs. You can also compensate for a too-tall desk by raising your chair height, but if you do that, be sure to pay attention to the way that affects your overall position. You may need to add a footrest to maintain proper leg position.

Sitting in Style (and Comfort)

A well-designed chair is worth every penny you spend on it, but only if you take advantage of its capabilities. Ideally, you should be able to independently alter the seat height and angle, back rest, and arm rests.

To properly adjust your chair, begin by raising the height until your knees are around a 90 degree (right) greater angle, and your feet are resting flat on the floor. If the front edge of the seat is running into the backs of your legs, slightly tilt the seat pan (the flat part you sit on) forward to relieve the pressure. It's best if your knees are slightly lower than your hips.

Your lower back (the lumbar area) has a slight natural forward curve. Raise or lower the backrest until it supports that waist-level curve and allows you to lean back comfortably.

Armrest use is a matter of personal preference.

"For many women, armrests are too wide apart for comfortable use unless it is just occasional," warns ergonomics consultant Carol Stuart-Buttle, CPE.

If you have armrests, adjust them to a height just below elbow level. A lower setting may encourage you to slouch down. A higher one is likely to position your shoulders in a perpetual shrug. Don't use the armrests when you type; save them for breaks, instead.

If your chair is too low in relation to your work surface, raise it until your knees are within a few inches of the underside of the desk or work surface. Then use a footrest (a thick book will often do the trick) to elevate your feet until they comfortably rest flat and your knees are returned to about a 90 degree (or greater) angle.

Always test drive a chair before buying it. You can't tell by reading a catalog how easily a chair will adjust to fit your body shape or how comfortable it really is. Try it out in the store or, even better, ask if you can try it out for a few days.

The Equipment

Place your monitor 1½-2 feet away from your eyes, so that the top of the screen is at eye level. If you've got it sitting on top of your computer's system unit, it's probably too high. Monitor glare is a frequent cause of eyestrain. To avoid it, position your workstation so that your light source isn't directly in front or behind it. If that doesn't alleviate the glare, consider purchasing a glare filter.

Keyboard adjustment is especially important.

"Get the keyboard low enough so that your elbows hang comfortably at your sides, and forearms and hands are floating easily over the keyboard," advises Cathleen M. Smith, Ergonomics & Human Factors Specialist at Netscape Communications. Your wrists should be relatively straight.

"Wrist rests should be used to 'rest' on intermittently between typing sets only, not actually while typing," says Smith.

Place your mouse pad where you can reach it without stretching or turning at an awkward angle. Use the mouse pad; it will increase the responsiveness of the mouse and reduce the distance you have to move it. If you spend lots of time using the mouse and find it uncomfortable, consider replacing it with an alternative device such as a trackball or touchpad. As with the keyboard, float over the mouse/trackball, trying not to anchor the wrist to the surface upon which it sits.

It's All About You

Once you've adjusted your workstation, you need to adjust your work habits. Although computer tasks can be very engrossing, it's important to take frequent breaks. Every 10-15 minutes, look away from the computer screen and focus your eyes on something farther away. Don't sit for longer than two hours without getting up and stretching, which gets your circulation going and relieves cramped muscles.

"Taking breaks is often perceived as losing productive time. But if you take a few minutes to roll the shoulders, shake out the hands, look to the distance, and change your back position, then you will be more productive overall in the day and in the long run," says Stuart-Buttle.

If you share your computer space with someone else, take the time to adjust the furniture and equipment each time you sit down.

"As much as ergonomics fits the environment to the user, there is always that human element that requires the individuals to take an active role in improving work habits," says Smith. It may cost a few minutes up front, but better to spend those minutes in comfort than in pain and in a healthcare provider's waiting room.