Programmers (and other full time computer users) should be careful with this and similar yarn-based hobbies. I gave myself an apparently permanent RSI issue in my shoulder from knitting with bad technique (had too much tension in my yarn I think). I learned from you tube videos, a human probably could have told me I was doing it wrong but I didn't ask anyone.

The injury does affect my computer use, when it gets real bad I have to switch my mouse pad to the other side of my desk. I haven't knitted in years and its still there.