While posture, the quality of your chair and the ergonomics of the mouse and keyboard can be big factors in how long you can sit at your desk, for me, it always comes down to eye strain. Without question, if I stare at my screen for more than four hours straight, I'm guaranteed to have a headache. So how can one battle eye strain? That's the very question I put to my optometrist the last time I went to visit. Here are a few quick methods he recommended:

  • Move any lighting that's behind your monitor and try to reduce the amount of overhead light shining downward. If possible, place lights on the desk alongside the computer instead, so as to reduce reflections and glare.
  • Just because you moved your lights doesn't mean you should be working in a dark room. Make sure it's properly lit. An easy way to tell if a room is lit well enough is to simply determine what's brightest in the room. If your monitor is the brightest thing in the room, that's a bad sign. Get another lamp, or a higher watt light bulb for your lamps.
  • Dry rooms can dry out eyes, exacerbating whatever effect the monitor is having. Add a small humidifier to dry rooms, or if a room is only a little bit dry, get a large plant. Plants naturally add moisture to the air.
  • If all else fails, schedule five minute breaks. This can mean simply walking away from the screen for a moment, or even just closing your eyes while sitting at your desk and listening to a quick song.