I thing I like best about yoga is that while you appear to be still  in a posture, it is always dynamic with micro moves.  Not only do these micro moves improve your alignment, but thinking about the hundreds available leave your brain no time to think about anything else.   One such move happened a couple of weeks ago while in upward facing dog.  It was amazing how much more space was realized when, in the pose, I pulled my hands towards my body.  My hands really didn’t move, but the intent and isometrics really made my heart shine through.