As the track season winds down in the spring, distance runners enter a time that sport scientists call the transitional phase in the annual plan. More specifically, it’s the time where summer training for cross country becomes the priority. Track is an unusual sport in that there is no one time that all of the athletes are finished with their season.  An athlete that finishes up with a junior varsity meet or a sophomore championship meet may end their season more than a month earlier than the athlete competing at the state championships.  And of course the very best runners may go on to run at an all-star meet or USATF Junior Nationals.  It is just not a clean ending for everybody.  The transitional phase serves…