If you sit and don't engage your reptilian moving-about system it will engage anyway. You'll be looking for distractions in front of you. And then you'll be stu

If you sit and don't engage your reptilian moving-about system it will engage anyway. You'll be looking for distractions in front of you. And then you'll be stuck on those, tripping out. On the other hand if you were to step out for 15 minutes and then come back, just walking and looking around, thinking of what you'll be doing when back at the computer; then when you're back you'll have something to do. Good luck not getting stuck doing that. Because you will. Turn off all notifications, time-box all calls and emails to twice a day, and reduce the use of color in the UI. Don't let yourself be prompted into getting stuck on something. You have your own agenda and the world around you can manage for 3-4 hours without your input. It really can. Make sure it can. Being prepared is half the job.