I work at a keyboard for a living and I have abused my wrists by spending too many hours at a keyboard playing games, writing, and other computer based activities for pleasure - I'm looking at you, MMOs, World of Tanks, Google+ and Twitter.
Now I am paying the price. I end up in pain almost every single day by the end of the work day. Weekends trying to do mapping and blogging and just having fun has to be carefully monitored.
Make sure you take care of your wrists. Take breaks. Use proper ergonomics. When your wrists get sore - it's a sign to stop and take a break. If you constantly get sore change what you are doing, how you are doing it, and for how long you do it.
Image from public domain images Keyboard by Petr Kratochvil