Of all the Chi Running focuses the ones that contain directions to help keep your column are the most important to instate when beginning your practice. Your column is made up of your shoulders, hips, and ankles. When they are properly aligned you are in a position that will allow your leg muscles to relax. This relaxation is made possible by your body being supported by its bones, tendons, and ligaments. The support these properly aligned structures provide while you are running reduces muscle usage which makes you a more efficient runner. Having great posture allows for more volume of air exchange as opposed to being bent at the waste. You can experience an increase in your tidal volume as much as 30% by keeping proper alignment. Think about most runners near the end of a race that are bent forward at the waste and how much lactic acid they have in their body. Wouldn't having thirty percent more oxygen help with all that acid in their muscles?
Posture for the Chi Runner also includes another type of alignment which is directional. To be an efficient runner you should have everything moving in the direction your headed which entails keeping your feet, shoulders, and arms pointed forward. Splaying your feet to the side or your having your arms cross your center cause your body to work harder. If your shoulders are rotating your lower body must work harder to overcome this movement. On those long runs that energy conservation or usage could be the difference between a PR or the beginning of an injury from misaligned repetitive movement. On your runs have you ever paid attention to how you are moving? Have you had a video analysis done so you can learn and see how you move? I can tell you that prior to me practicing Chi Running I never gave it much thought. After seeing myself running on video what I thought I looked like was very different from reality.
If you choose to become mindful of your posture alignment remember that you can practice it all day not just when you are running or walking. The more times you work at instating the focuses you develop a deeper muscle memory that will be there for you when you need it most on those challenging runs. Remember Chi does not flow if your muscle are tight. The way to relaxed muscle begins with proper alignment.