Lyle Underwood is a graduate of Foley High School and Florence State College. He was a standout football player for the Foley Lions and was a letterman in college (1958-59).

Underwood spent 14 years as the head football coach at Baldwin County High School in Bay Minette from 1966-1979. His Tigers combined for a 101-40-3 record during his tenure there. His teams qualified for the playoffs five times and won two area titles.

Underwood coached two teams that finished the regular season undefeated in 1973 and 1976. He also served as an assistant football coach at Fairhope for four years and East Mississippi Junior College for two years.

Underwood was named Baldwin County coach of the year four times, he is a member of the Foley High School and Baldwin County Athletic Halls of Fame. He is also a member of the Baldwin County Varsity Coaches Association Hall of Fame.

He was inducted into the Alabama High School Athletic Associations Hall of Fame in 2011.