I just started learning ChiWalking and ChiRunning, and I have been focussing on posture and pelvic tilt, because I know that these are problems I have. I have made wonderful progress in learning good posture while walking, and I can now walk over an hour in an effortless fashion. But when I visited a museum on the weekend, I was faced with a new challenge: how to stand still with good posture and not get a tired back. After 40 minutes, I was a wreck, and I had to leave. Why can I walk with good posture and have no back problems, but standing in one spot seems to be so much more difficult?