Quick layman’s ergonomics for computer users
If working with a mouse and keyboard causes you physical pain, please see a professional ergonomist or medical doctor. I am neither, but because I have designed some novel keyboards for ergonomic purposes, I have learned some of the specifics without knowing the basics. People ask for my advice, and here’s what I usually say.
In this article, I’m going to be using the term “RSI” (repetitive strain injury) for any kind of physical pain that comes creeping up on you over time as an occupational hazard of typing. This includes everything from back pain to cubital and carpal tunnel syndrome. There are lots of impairments and diseases, including autoimmune rheumatic diseases, that can provoke and exacerbate RSI. About these, I know very little. Again, take what I say with a grain of salt and consult a professional.
Breaking yourself down and building yourself up
The first simplistic thing to learn about computer ergonomy is that it’s salutogenic, meaning it promotes wellness. Crucially, it does not cure disease. No keyboard, no matter how awesome, will cure RSI.
The pain of RSI is the pain of straightforward nociception. It’s your peripheral nervous system informing your central nervous system that your body has been damaged. Your body gradually recovers from such damage as it does from any injury.
There are general measures you can take to recover from a wound, such as physical therapy and not poking at the wound. Beyond that, your rate of recovery is pretty much a function of your age. That is especially true of RSI, which is internal and only rarely permanent.
What computer ergonomy does is to reduce the rate at which you wear yourself down. At best, a good keyboard will help decrease the rate of injury to a point below the rate of recovery. The differences are usually so small that the net effect is slow and subtle.
Promoting wellness is mostly about good habits. What makes a good habit can be counterintuitive, because the vast majority of us humans are complacent and live in cheaply constructed environments. These environments are unlike the East African Rift System of two million years ago, where nature made humans.
In the wrong environment, even the most frequent exercise is not enough to maintain good health. In 2018, an elite endurance swimmer named Benoît Lecomte swam on average for 5.8 hours per day over a period of 159 days. Despite adequate nutrition and the extreme level of exercise, Lecomte lost about 20–25% of the mass of his heart over that period.1 Intense swimming over a shorter period of time can strengthen heart muscle, but taken to an extreme—with water supporting the body of the swimmer and making him effectively weightless—the impact was negative.
Sitting is weird in the same way. We humans do better walking, standing, squatting and lying down to sleep than we do sitting. Lifestyle diseases abound for those who spend all their time in cars, on sofas and at traditional sit-only desks. The most basic thing you can do to prevent RSI is to move around, to some degree lower than Lecomte’s.
I’m tall and therefore naturally prone to back pain. In my experience, vigorous biking for 70 minutes every weekday is adequate cardio, but it’s not enough to prevent back pain if you are otherwise sedentary. Since the age of about 33, even with the finest keyboards in the world, I’ve had to walk and jog regularly. That was an unpleasant surprise, but it’s a chance to get out into nature and watch amazing sunrises.
Having established that people cannot be healthy staying in one place, some ergonomists have adopted the mnemonic slogan that “your best position is your next position”, meaning that you need to vary even your posture. Because they are flat, rather than biased toward a specific hand position, traditional keyboards make it easy to vary your posture. Traditional flat keyboards have also been the subject of a lot of research to determine a good “starting” position that you can vary. It’s described in roughly these terms:
To prevent injury, the user should keep the wrist in a neutral position. That is, the line from the hand to the forearm should be straight. The hand may be slightly lower than the forearm. But the hand should never be higher, and the wrist should not be cocked. The keyboard should be positioned relatively low, keeping the hand slightly lower than the elbow. A wrist pad can be used to support the wrist.2
Nowadays, there are excellent “roller” mice that integrate with ordinary office keyboards to further ease strain on moving your dominant hand between keyboard and mouse. Some experts recommend keeping the keyboard itself as close to the level of your thighs as possible. Again, that’s easy to do with consumer-grade membrane keyboards3 that are light, thin, and broad.
Illustrations of the proper posture commonly include the right way to position your screen to keep your neck and back straight. That’s very helpful, and so is a good chair. A Håg Capisco and a motorized sit-stand desk provide ample opportunities to vary your posture throughout the day.
Most people never do so much typing that the specifics of their equipment really matters beyond these basics. Ordinary membrane keyboards, especially with a roller mouse, are a metastable design. They represent a compromise solution that serves a variety of interests well enough. If you find that you have adopted a proper posture, and varied it, and you exercise to stay fit, but you still develop RSI on a membrane keyboard, then you—like me—fall outside the range of that compromise.
Typing without looking
As a historical sidebar, the desktop computer revolution of the 1990s left touch typing a rare skill. The smartphone revolution is set to keep it that way. Children these days rarely type and few will learn to do it well. As a result, most people—young and old—avoid typing, and when they do get to typing, they are so slow at it that the body doesn’t take much damage. With basic ergonomics, any strain produces a feedback loop that keeps actual pain rare, but for those who do develop RSI this way, there is no obvious way off the beaten path.
If you want to be both comfortable and productive you will want to learn touch typing. It reduces the amount of time and strain required to produce each correctly typed word, but as with any increase in productivity, the total strain per second is constant or worse, especially on the QWERTY layout. Touch typing prevents RSI only if you are patient, find some novel equipment, or use a different keyboard layout. I recommend the Colemak layout.
Beyond the pale
In addition to being tall, I am an unusually frequent user of keyboards: A professional programmer and diligent writer of documentation, email, reviews, etc. I use keyboard-controlled tiling window managers like Sway, keyboard-controlled browsers like Vimium, and so on. I am not out to break any speed records, but I lack the natural protection from RSI that comes with disuse and slowness, and I now find QWERTY frustrating.
There are traditional solutions to problems like mine. For narrow use cases like court hearings, there are stenography keyboards, but you would need heavy adaptations of that design for programming. For less narrow uses in professional data entry, there are various chorded designs like the syllabic Velotype, which is still in business. For general use, that is typing one character at a time, the world leader at one time was Maltron, still in business since the 1970s, but now interesting mainly for people with disabilities.
Non-traditional solutions have exploded over the last few years. I tested a few before I started designing my own. As of September 2021 I use one Concertina at home and another Concertina at work, without any problems. Inventing the Concertina has stopped my own tumbling down the rabbit hole for now.
If specialized hardware like a Concertina is a daunting prospect, consider going without a keyboard. There are inspiring cases of voice control for programming, like this one by Josh W. Comeau, and this 2018 talk by Boudewijn Aasman. Both are programmers, but their solutions could be adapted for other purposes. There are also software keyboards for touchscreens that look impressive and seem to require minimal movement, as long as you can go without the feedback of tangible keys. There’s a steep learning curve, but check out this quick 2015 demo of the PentiKeyboard Android app, and Adatype. If you’re willing to wait, brain-computer interfaces are making steady advances.4
Conclusion: Safety first
The body is complex enough that, once you develop RSI, it can be difficult to tell what the trend is at any given moment. In my experience prototyping new keyboard designs, a subtle mistake in the placement of a key, by just a millimetre or two, can cause a serious problem. It would take weeks for me to pinpoint the exact problem, and weeks to recover once I had a new prototype that eliminated the error.
Such obscure experiments are probably irrelevant to you. If you want to be both fast and comfortable at the same time, then by all means explore ongoing developments. If not, mind your general health and observe the most common, science-based advice and slogans of the professionals. It’s good advice.