Arlen Quincy Harris Sr. (born April 22, 1980) is a former NFL running back who played for the St. Louis Rams, Detroit Lions, and the Atlanta Falcons.

He won a MSHSAA State Championship at Lutheran St. Charles in 2021 as the head varsity coach, named Coach of the Year along with his oldest son AJ receiving Offensive POY and his youngest son Ayden Defensive POY.

Arlen was born in Chester, Pennsylvania,[1] and was considered one of the top 3 running backs coming out of Downingtown High School where he won a PIAA State Championship and broke Tony Dorsett's rushing record.

He played three seasons with the Rams, starting three games and scoring three touchdowns versus the Steelers' #1 defense.

[4] He ended his career with the Atlanta Falcons with a knee injury in the last pre-season game against the Baltimore Ravens.