[adrianwaj]

I'm not sure. Often I recline the chair and put my feet up on the desk to the side of the screen. I think this is healthy and it feels right. I recommend trying it. I once saw that NASA determined that the correct way to position astronauts (on a trip to Mars) was lying on back but with feet above head and head raised. Recently installed http://stereopsis.com/flux/ to shade the screen at night - so far so good. Last step is to make sure I am grounded: I'll need to locate equipment to do (and test) this.