what does j mean in track and field
Athletics abbreviations When a J is added, it indicates a junior record (if a junior does not reach their 20th birthday in the calendar year of the mark)
Walk-on (sports) The term walk-on is used in sports, particularly American college athletics, to describe an athlete who becomes part of a team without being recruited beforehand or awarded an athletic scholarship. This results in the differentiation between "walk-on" players and "scholarship" players.