More and more of us spend long hours at work or at home sitting in computer chairs. Unfortunately, the human body wasn't designed to sit still for long stretches. Many workers and ardent computer gamers suffer from all kinds of ailments, including Carpal Tunnel Syndrome and back pain. If you're in pain at the end of each day, your computer chair might be the culprit.

Office furniture should do more than just hold your papers and offer space to rest your laptop on. After years of grumbles from stiff-necked workers, furniture designers started coming up with ideas that were more ergonomic. Today's office furniture conforms more closely to the natural shape of the human body and puts less stress on the back and shoulders.

Still, there are some pretty bad computer chairs out there. To find out if your computer chair is the best choice for your comfort, ask yourself these questions:

• Does my lower back hurt when I stand up from the chair?

• Do I often have tension knots in my back and shoulders?

• Is it easy to adjust my chair into different positions as needed?

• Have I suffered from Carpal Tunnel Syndrome or other repeated stress injuries?

Poor posture can lead to any of these ailments, so always practice proper typing and sitting positions. But if posture alone isn't helping, your computer chair could be hindering you. Fortunately, ergonomics experts have some tips on what to look for in computer chairs.

The most important thing to remember is that there is no “one size fits all” computer chair. What works well for your friend might not be so comfortable for you. For instance, your co-worker might enjoy one of the “kneeling” type computer chairs, but your knees might not appreciate the pressure. Therefore, it's important to shop around and try out the different ergonomic chairs to find one you can live with day after day.

For a good basic design, look for computer chairs with high backs that curve slightly inward in the lower lumbar region. Arm rests should be flat, comfortable, and at a good proportional height to allow you to type without straining your wrists. A well-cushioned seat is also important; nobody wants to sit on a hard chair for hours. Look for chairs that offer plenty of support in the seat and back.

Adjustable chairs are a good choice for people who get stiff or sore after sitting for long periods of time. They're also the best choice for workstations used by people of various heights. A reclining mechanism allows the worker to lean back and ease the strain on their spine during breaks. Rollers may or may not be a good idea; it's advisable to get up and move around every half hour or so, but rollers make it a little too convenient to retrieve objects without getting out of the chair.

The most important component of ergonomic office furniture is the user. No chair can make up for constant bad posture. Sit straight while you work, and stand up frequently to stretch. Your joints will appreciate it.