Eighteen-year-old Helen Stephens, nicknamed "Fulton Flash" after her birthplace of Fulton, Missouri, ran in the 100 m dash in the 1936 Summer Olympics in Berlin ... and won.
As was the custom at the time, Stephens made the obligatory visit to Hitler's box after winning gold. In his Complete Book of the Summer Olympics, David Wallechinsky wrote:
She offered a firm handshake (Americans didn't give the Nazi salute), but Hitler offered a firm grope. "He gets a hold of my fanny," the Fulton Flash said, "and he begins to squeeze and pinch and hug me up, and he said, 'You're a true Aryan type. You should be running for Germany.'"
Then Hitler laid on the big offer: a weekend at his retreat in Berchtesgaden. She turned him down. (Source)
Side note: At the Olympics, Helen Stephens beat the reigning champ, Stanislawa Walasiewicz of Poland and there were accusations that Helen was actually a man. After a genital inspection proved otherwise, the matter was dropped.
Walasiewicz, who subsequently changed her name to Stella Walsh was killed in an armed robbery many decades later. In an ironic twist of fate, the autopsy showed that she actually had male genitalia (though she had both XX and XY pair of chromosomes). From that point on, she was often referred to as "Stella the Fella."