Being a desk jockey isn't always glamorous, but lots of important work is done while sitting in an office chair. Unfortunately, that kind of extended seated work is bad for your health.
The litany of potential problems includes a heightened risk of cardiovascular disease, diabetes, and other chronic ailments. It's also hard on the spine and a common source of work-related musculoskeletal disorders (MSDs). Not to mention all the costs associated with these types of ergonomic injuries.
Being in very good physical shape can reduce the likelihood of developing an MSD, but this is by no means a guarantee. The U.S. Marine Corps has some very fit members, yet one of their greatest sources of loss are lower back ailments caused by seated work.
Are the Workstation Components Adjustable?
It's impossible to eliminate all extended sitting sessions, but creating an ergonomically friendly workstation can significantly reduce risks.
One of the best ways to accomplish this is by having multiple adjustable components.
Consider something simple like typing at the computer. To do it without risk of injury, the wrists should be as straight as possible, with the elbows roughly level with the desk surface. Lowering the height of the chair can make this easier, but this might bring the chair so low that looking up at the non-adjustable monitor causes eye and neck discomfort.
This causes a dilemma: do you protect the wrists or protect the neck? Workstation components that are easily adjustable eliminate this conundrum and others like it.
Office Chair Adjustments for Improved Ergonomics
The chair's seat height should be adjustable so the user's thighs can be approximately parallel with the floor. This won't be the most comfortable position for everybody, but it's an anatomically neutral starting point and small changes can be made from there.
Likewise, the seat height should allow the worker's feet to be flat on the floor. If the feet can't reach the floor, the legs won't be supported and they'll be held aloft by the seat pan. The pressure this places on the upper legs can cause discomfort and impair blood circulation. If the seat can't be adjusted sufficiently, a footrest can help solve this problem.
A lower back adjustment for lumbar support is available on some chairs, which is a great feature since so many seat-related issues involve this part of the body.
Arm rests with adjustable height will allow the elbows to be at approximately 90 degrees, which is a neutral position. Elbows shouldn’t be too far out laterally from the torso – the farther away from the torso they get, the farther they will be from a natural position and discomfort and strain will result. Having the elbows close to the torso is preferred, but they do not have to be pinned to the rib cage.
If the arm rests are also laterally adjustable, then the worker can have support for their arms while also be in a comfortable position suitable to their particular body shape. It is not necessary that the arm rest provide all of its support at the elbows – spreading out the surface contact area helps to reduce discomfort and allow for more flexibility in positioning.
Keyboards, Mice, and Wrists
Our hands and wrists can only do the things they do because of their complex biomechanical hardware – the bones, tendons, muscles, and blood vessels that make it all work. Unfortunately, this hardware is prone to damage when it gets overused or used improperly.
Thankfully, some simple precautions can help to avoid the onset of MSDs affecting the wrists.
First, the keyboard should be located on the desk so the elbows are at roughly 90 degrees and the wrists are as straight as possible when using it. If the keyboard is too high, the user will need to raise their elbows to reach, straining the arms and shoulders. If the keyboard is too low, the arms will be angled downward to reach it and the wrists will likely be bent upward while using it, which should be avoided.
The mouse should be positioned close to the worker’s side and at a height where the arm will hang naturally, not held up in an unsupported manner. As when using a keyboard, the wrist should be as straight as possible.
When moving the mouse around, it is ideal to have the arm and shoulder do most of the movement and not by keeping the arm stationary and bending the wrist to make mouse movements.
A keyboard and mouse rest, such as a gel pad, can help to keep the wrists straight, but this should not automatically be the first option selected when dealing with wrist pain. The rest itself will result in pressure being applied to the surface area of the wrist, which could impair blood circulation and cause discomfort. A simple chair adjustment to get the elbows into position is a better first option.
(Learn more in What Is Lean Ergonomics?)
Line of Sight and Neck Pain
Much of the common guidance for workstation ergonomics addresses chairs, keyboards, and mice. Rightly so, as MSDs of the lower back and wrists are very common. But MSDs involving the cervical vertebrae of the upper spine and all sorts of problems involving the eyeballs are also common and should be addressed.
Assume there are imaginary laser beams coming from the eyeballs that illustrate a worker’s line of sight. Ideally, the laser beams will be roughly perpendicular to the spine. If they are, it means the cervical vertebrae in the neck should be in line with the spine. It also means the eyeballs aren’t peering up or down too much but are in a neutral position.
To illustrate this, relax your eyes and close them for a few seconds as if you were going to take a nap in your office chair (a common side effect of reading ergonomics articles). When you open your eyes, the line of sight you have is due to the neutral and natural position of the eyeballs. If what a worker looks at for several hours a day can be positioned within that general line of sight, eye discomfort and the frequency of headaches will be minimized.
A focal point slightly below the height of the eyes results in a natural, neutral, and comfortable position. To test this, read some text that’s slightly above the height of your eyes while keeping the neck’s position fixed; move only your eyes to track the text. Then, rest your eyes for a minute or so. Next, do the same thing but with the text position slightly below a horizontal plane with your eyes. Notice a difference in eye comfort or strain?
Another way of illustrating this is the typical line of sight while walking. Most humans do not walk down the street with their necks and eyes oriented so their imaginary eyeball laser beams are 100% perpendicular with the ground – most have a line of sight that is slightly below a horizontal plane with the eyes. As humans evolved, avoiding trip hazards was very important to survival. So, a line of sight a little below the horizontal plane with the eyes allowed a good scan of the horizon ahead and superb focus on the ground far enough in advance to avoid stepping on a wolverine or falling into a hole.
For the reasons above, a very common guideline for monitor placement is to have the top of the monitor roughly level with the eyes, since almost everything viewed in such a position will be slightly below eye height.
The focal distance is also very important. 15 to 25 inches from the eyes is a good starting point. When using multiple monitors, minimize the difference in their distances from the eyes to reduce discomfort and prevent headaches caused by continuously refocusing the eyes.
(Learn more in How Wearables Can Change Behavior and Reduce Ergonomic Injuries)
Move Around!
It's difficult to give universal ergonomic advice. One person's comfortable position may be bothersome to another.
There is, however, one piece of ergonomic advice that applies to everyone: move!
Sitting in the exact same position for half a day should be avoided. Even slight and seemingly insignificant shifts in posture can help to accomplish this.
It's important to note that this is still a compromise. Even when seated comfortably and following every ergonomic guideline, sitting in one spot for an extended period of time is detrimental to the body.
If possible, everyone should get out of their chair for a minute or two every 20 to 30 minutes. Standing up and walking around during calls is also a great opportunity to shake off the chair for a while. It's not exactly a fitness class and that kind of movement isn't going to get anyone in peak physical shape, but it gets the joints moving and the blood flowing and that truly does the body good.
Sitting at a workstation for hours every day isn't ideal, but it's a mode of work that isn't going away anytime soon. While it's never great your body, it's critical to take steps (including literally walking around) to ease the toll it takes on the joints and muscles and improve everyone's comfort and productivity.