I was going back and reading Mark's blog posts and my attention was snagged by the post How to Recognize and Tap Into the Power of Flow. It soon became apparent to me, as an introvert, that flow is a mechanism that I use almost daily (usually through some form of exercise) to replenish my energy that has been drained by the daily grind/stressors. Flow seems to me to be possibly easier to attain for introverts as, in general, solo activities give energy back versus extroverts gaining energy from social interactions.

So to my fellow introverts, and those extroverts that may want to learn more about your "opposites", here is just one of what I'm sure are many blogs/resources on the Interwebs.

The Introvert's Corner | Psychology Today