I’ve done something like this before, progressive relaxation of your muscles (although I didn’t tense them up first) to help your body relax.  I never could figure out at way to “turn off my brain” when my brain is awake so it can solve some problem.   Apparently repeating an article with no meaning itself is enough to disengage the thought process.  Try repeating “the” in your mind.  Eventually the logic of it causes you to go numb. Lifehacker has more on the story:  http://lifehacker.com/software/sleep/get-to-sleep-faster-by-tensing-up-and-repeating-the-327468.php

Just what the Dr. ordered to get me to slee……