She is a two-time medalist at the 2019 Pan American Games in Lima, Peru and won the silver medal at the 2024 Summer Olympics in 400 m hurdles event.

[5] In 2016, she won the gold medal in the women's 400 metres hurdles event, with a personal best of 55.20s, at the 2016 IAAF World U20 Championships held in Bydgoszcz, Poland.

[12] At the 2020 United States Olympic Trials for track and field on June 27, 2021, Cockrell placed third in the women's 400-meter hurdles event to qualify for the team alongside Sydney McLaughlin and Dalilah Muhammad.

[20] Cockrell has been an outspoken advocate for the mental health of student-athletes after suffering a hamstring injury on the first day of the 2019 NCAA Division I Indoor Track and Field Championships in which she blamed herself for her school's loss in the team competition.

After exhibiting severe symptoms of depression and suicidal tendencies, she eventually sought assistance from her friends, her head coach, and a sports psychologist, all of whom she thanked in her student-athlete graduation speech at USC that later went viral.