How to Sit More Comfortably on the Job

If you spend most of your workday sitting down, you can do your body a favor by sitting properly in a chair designed for maximum support and comfort.

An ergonomically designed chair—one that supports your back and the rest of your body comfortably—should have the following characteristics:

• The seat pan, or the area on which you sit, should be comfortable and at least an inch wider than your hips and thighs on either side, say experts on ergonomics at Cornell University. Your thighs should be able to extend past the edge of the seat pan. If the seat pan is too long, the edge will hit the back of your knees, or you won't be able to sit back in the chair. The better chairs have a "waterfall" front edge, which slopes down and avoids hitting your knees.

• The chair height should be easily adjustable. The better chairs have a pneumatic adjustment that allows you to adjust the height of the chair while you are sitting on it.

• The lumbar or lower back rest should be comfortable. The better chairs allow you to adjust the lumbar support up or down, or backward or forward, depending on your build. Even a fixed lumbar support is fine, as long as it feels comfortable when you sit back against it, Cornell experts say.

• Besides lumber support, the chair should also provide support for the mid- and upper back.

• The cushioning in the seat pan should provide enough support for a comfortable sit after an hour—or two. Low-density foam cushioning can become permanently deformed after a period of time, which decreases its support. If the cushioning isn't adequate, you may feel fatigue in the back and hips, Cornell experts say.

• The chair should allow you to recline, yet still provide adequate support. Cornell experts say sitting perfectly upright isn't recommended over a long period. A more healthy posture is one that reclines slightly at 100 to 110 degrees.

• The chair should have at least five spokes radiating from a pedestal base. The casters should allow the chair to move smoothly over the floor.

Other features

• Consider whether you need armrests on your chair. If so, they should be broad and cushioned, Cornell experts say. You should be able to adjust them easily, both higher and lower, and closer and farther apart.

• You may need a footrest if you are not able to lower the chair enough to keep your feet flat on the floor.

• Consider which chair covering you prefer. Vinyl is easy to keep clean, but it doesn't "breathe." Moisture can accumulate under the thighs as the vinyl-covered chair heats up, Cornell experts say. Cloth upholstery breathes more, but is more difficult to keep clean.

Adjust the chair

Taking the time to fine-tune your chair to fit you is extremely important. Be sure to adjust the seat height so your feet are resting flat on the floor when you sit back. Use a footrest if you're sitting at a high desk or in a chair that can't be lowered. Adjust the seat angle so it tilts down slightly.

The back support should be aimed at the lower (lumbar) curve of the spine, and the armrests should be adjusted so your arms are at right angles when you're sitting up straight.

If you sit for long hours, you can help avoid pain if you get up and move around as often as you can. Some ideas:

• Stop every hour to stand and stretch.

• Walk to the water fountain or break room every hour or two.

• Stand up when you're talking on the phone or filing.

• Don't eat lunch at your desk; walk to a restaurant or a break room.