I found this description (and visual impression) to be so interesting and helpful, because it can guide us in understanding where we're off balance or not present in our bodies or lives. I recalled of a moment recently when I was at a beautiful lake, doing something I love to do---relaxing, and enjoying a good book. The only problem was that I had stopped understanding what I was reading and I was ignoring the beautiful surroundings, the perfect temperature, the breeze. This, I thought, was a perfect example of being behind myself. What I needed to do was put down the book and get with where I was in time and space and feeling in that moment.
An example of being ahead of myself occurred later that day, when my husband and daughter announced that they were going to swim the 3/4 of a mile cross the lake, and back. I found myself feeling a little nervous and wanting to tell them how to do it. Then I got busy mentally casting protective light around them. Control City. I was projecting myself into their business off of my own center.
If you think about the people you know, you can see this concept playing out in their body language, words, actions, and life circumstances. Do you know someone who's always in your face? Or someone who's so laid back that they don't get anything done? Some people take over a place while others recede into the woodwork.
Perhaps you've taken yoga classes and remember doing the Mountain Pose. It's mostly just standing up straight, legs slightly apart and equally weighted, with arms resting at your sides. This stance embodies being present in the moment and centered in your body. (Try it sometime---it can help you feel grounded and strong).
So where are you right now? Centered in you body? Ahead of yourself? Behind yourself? Perhaps floating above your body, or buried in the ground? Asking yourself this question every now and then can serve as a quick and effective practice for getting back to your center and learning when to step forward and when to step back.