There is a mystical feeling often written about but rarely experienced called Flow.  To quote wikipedia:

Flow is the mental state of operation in which a person in an activity is fully immersed in a feeling of energized focus, full involvement, and success in the process of the activity.

Flow is the point when you realize you’ve been working on something for hours and have more energy than when you started.  It’s when you lose track of time so completely that your partner with a cold sleeps in until 3pm and you don’t notice.  It’s when you have great ideas, but not so many that you can’t process them, use them and work them.

I was lucky enough to hit that yesterday; I spent 9 hours working on my dissertation proposal and felt great.  I had tons of energy when I was done and only stopped because there was a TV show on that I wanted to see.  Then I woke up this morning (a holiday in the U.S.) at 7am ready to get back to work.

If I could bottle this feeling it would make me incredibly wealthy and put red bull out of business.  Of course, that isn’t possible.  But there are some tricks to getting this feeling more often and hanging on to it once you do get it:

1. Make sure your goals for the session are clear.  Ambiguity saps focus, which in turn prevents you from achieving flow.  For me, I have a self-imposed deadline to send a draft to my chair by the end of today.   I have a short list of things that need to be included in that and a small pile of articles that I need to review and write about for the draft.  By having specific, constrained goals I take mental energy off of “what do I need to do next” and can focus it on my work.
2. Choose tasks that are challenging, but possible.  You need to feel you can accomplish what you are setting out to do but, at the same time, cannot feel that the tasks are too simple.  There must be a balance between challenge and self-efficacy (your view of your ability to meet those challenges).
3. There should be an immediate feedback mechanism.  You need a way to know if you are going off track quickly, so your task should have some way for you to judge built in.  Most of what I am working on is the lit review, and I have found that reading the abstract of an article, then flipping through my lit review to where a reference to this article would go is a great way of getting quick feedback.  If I can’t figure out where an article fits in the chapter, it probably doesn’t and I should set it aside.  I also have taken to reading my work out loud to my dogs.  They are happy for the attention and I can quickly hear any awkward phrasing.
4. Make sure you have some time.  Flow doesn’t just start when your fingers hit the keyboard; you are going to need to work into it.  So make sure you give yourself some time to get into the process.  So while taking regular breaks is a good thing, give yourself some time to get into the work before the first one.
5. Don’t force it.  Anxiety is the enemy of flow, so getting anxious about not reaching a state of flow is about the worst possible thing you can do.  Relax and focus on the work.  Flow will come.