To sustain our daily workload, we need strong mental focus.  Watch the video below, then come back here to finish reading.  Did you catch this quote: “mastery isn’t simply about the amount of practice.  It’s also the quality and effectiveness of that practice”?  Was your run today the kind of quality practice that would truly make you better?  This TED-Ed video, just like the ones on running form, is incredibly information-dense.  I’ve watched it a bunch of times, finding improved understanding each viewing.  How many times did you watch today’s running video?  Once is enough for today, but not enough for your lifetime as a good runner.  This practice video will come up multiple times.  Maybe watch it again.