1.I never have or hear that
2.I do not sure that I sit and type correctly when I use a computer or typewriter but I never use the computer for long periods of time that why I don't know do i have pains in any parts of your body from using the computer for long periods of time.
3.A. Don't using the computer for long time.
B.Buy a desk and a chair fit of you
C.Using the computer with a desk and a chair
D.Do some exercises after use the computer
E.Take some rest when use the computer for long time
vote for the best five
4.Yes,I agree
5.Yes,such as exercise of aim or exercise of hand.