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Comment by skocznymroczny | Hacker News Reader

Is there any science when it comes to ergonomy and tall keys? I would expect tall keys to be more damaging to wrists over time due to awkward position and longer travel time.

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Most of stress injury derives from the "time under tension" component which is not necessarily a matter of key travel distance. In this case it's a combination of switch mechanism and keycaps. Flat and light keycaps have less force at rest than tall, heavy keycaps. A higher resting force means the needed activation force is lower. In both cases, the switch is governing how much force is needed in total, and whether there's a "tactile bump" indicating activation before the switch bottoms out completely.

When the switch bottoms out, it's like your fingers have hit a wall: this is the norm with most membrane switch designs, and with linear mechanical switches, which are usually light. With tactile and clicky switches, the concept is to reduce bottoming out by indicating the activation with heavier force partway through the downstroke. A pairing of heavy keycaps and heavy tactile switches is often considered satisfying for typists because then the heft of the switch has been balanced out; a light tap will fling the key down past the tactile bump and spring it up without the same degree of muscle activation as a linear switch. And it is possible to have "too heavy" keycaps for the switch, which simply won't work(always activated).

With the key height, as well, what will matter is tension at rest, which will depend on overall posture. In theory you move the keyboard down if the keys are taller.

I learned that the proper way to type is with your hands floating above the keyboard, and resting your hands on a wrist rest when not typing. I don't always do it, but when I do, the height of the keyboard relative to the table becomes irrelevant, instead it's more about height of keys relative to my shoulders and maintaining right angled elbows.

Also, to me the Moonlander keyboard and its keycaps do not seem particularly tall.

I use a wrist rest as well.

It's hard to get a good wrist rest - they seem to last for a month or a year on amazon, and when I want to re-order, they are unavailable.

I have a memory foam one about 3-4" deep and the width of the keyboard. It is soft enough, lifts and supports my wrists and keeps them warm.

I think the wrist support on this moonlander keyboard is a good idea, but making it out of cold, hard plastic does not make it look comfortable.

I find gel wrist rest better. It has less give while still feeling soft to my wrists.

I used to use a gel wrist rest but the one I bought disappeared. I tried a plain foam one (glorious gaming), but it was too hard.

Be careful using wrist rests. The pressure can cause the carpal tunnel on the underside of your wrist to compress, increasing the friction on the tendons running through the tunnel and exacerbating or causing carpal tunnel syndrome. It's much much better to train your muscles and posture to keep your wrists from resting on a surface while you type.

I don’t know any science off the top of my head, but professional stenographers generally prefer low profile keys and short key caps. As someone who is recovering from RSI, short keys and light switches have been a god send.

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