Video: Watch Athing Mu Running World U20 Indoor 400m Record of 50.52

Video: Watch Athing Mu Running World U20 Indoor 400m Record of 50.52

Watch video highlights of American Athing Mu running to an outstanding time of 50.52 seconds to win the 400m at the Charlie Thomas Invitational in College Station. The time, which is the fastest in the world this year, is pending ratification, but it would break the world U20 indoor record.