Cain has always been fast. In fifth grade, she ran a 6:15 mile. Cain’s father, Charlie, an anesthesiologist, knew so little about track then that he had to ask Mary’s gym teacher if this was any good. In seventh grade, she ran a mile in 5:03, at which point, recalls Cain — a self-described nerd — “Everybody was like, what?! That wasn’t supposed to happen.” In ninth grade, Cain won the New York State 1,500-meter championship, breaking the freshman girls’ record. The summer after her sophomore year, she flew to the Junior World Championships in Barcelona and ran the 1,500 in 4:11.01, setting a new American high-school record for girls.
1,500 in 4:11?! That’s nuts.