They don't type hard enough :-)

Joke aside, I was mainly thinking about wrist problems. I think any normal sized, model-m layout or possibly split-layout keyboard with non-linear quality switches is ok.

If the finger joints hurts, I suppose a lower activation force might be good - I guess one might be Cherry MX Brown, but I don't personally like anything else than buckling spring...

The main message is that in my experience, laptops in your lap is the worst, and exercise helps.

Sure, thanks! its also interesting that RSI was much rarer when secretaries wuold type all day on heavy typewriters...