[tengwar2]

Nothing to do with weight. It's a cramp in the muscles of the hand from holding the pen and making fine movements for hours. I'm guessing you are from a generation after keyboard use became common, so you haven't encountered it.

[forgetfreeman]

Right and wrong. I am of a generation before common keyboard usage. As far as writers cramp goes, we all got it from time to time. At worst it was a minor nuisance compared to the skinned knees, bruises, and occasional broken bone that we racked up recreationally.