Mary Cain is an American middle-distance runner known for her achievements in track and field. Born on May 3, 1996, she gained national attention as a teenager when she became the youngest American woman to compete in the World Championships in 2013. Cain has set multiple records in her age group and has competed at various prestigious events, including the NCAA Championships. In 2019, Mary Cain became a prominent advocate for athlete mental health after sharing her experiences with the pressures of competitive sports. She has spoken out about the challenges faced by young female athletes, particularly regarding body image and the impact of coaching practices. Her story has sparked important conversations in the world of athletics.