Gretel Bergmann, now Margaret Bergmann Lambert, never got to the bottom of why Horst Ratjen became Dora
A new film tells the remarkable story of a female Jewish high jumper banned by the Nazis from the 1936 Olympics in Berlin - and whose team mate, it later turned out, was a man in disguise.
Berlin 36, due out this week, recounts how Gretel Bergmann was tipped for Olympic glory but was bumped off the German team at the last minute for fear that a gold-medal winning Jewish athlete would embarrass Hitler.
Instead, her "weird" room-mate Dora Ratjen competed. Dora gained only fourth place, but caused controversy two years later when a doctor discovered "she" was actually a he.
Gretel Bergmann emigrated to the US in 1937 and married a doctor, Bruno Lambert. Now aged 95, she still lives in New York, as Margaret Bergmann Lambert.
She described to the BBC's World Today the events of the 1930s, her reaction to finding out the truth about "Dora" and her anger at being unable to compete.
"I would have liked to compete, definitely," she said, "just to show what a Jewish girl can do.
"It wasn't for my own glory. It was just something that I needed to do because things were so horrible over there. We were shown as the worst people in the whole world and I just wanted to show that was a lie."
In the early 1930s, the teenage Bergmann was one of Germany's most promising female track and field athletes.
But in 1933, after the Nazis came to power, she was kicked out of her sports club and told she was no longer allowed to compete.
Aged 19, she left her family behind in Germany and went to Britain - quickly becoming the British national high jump champion.
But in 1934, she was pressured into returning to Germany, after the International Olympic Committee made Jewish participation a condition of Berlin hosting the 1936 Games.
"They forced me to. Somebody came to my father's house and was told by the Nazis that I must return to Germany and be a member of the Nazi Olympic team," she said.
"If I refused there would be trouble for my family living in Germany, so I packed my things and went home."
She was "very scared" at the prospect of having to compete in the Nazi team, she remembered.
"In the beginning I thought I am going to get myself out of it by competing really badly, but then I thought it would be a much better thing if a Jewish girl can show she can compete with anybody in the world."
But her participation in the 1936 Olympics was not to be. She was told at the last minute by the Nazi authorities she would not be competing because of "under performance".
"It was a very smart move [by the Germans]", she told the BBC, explaining that she only received the letter once the American team were on their flight to Germany - too late to boycott the Games.
"I was very angry that I could not do this for everybody who had peace in mind," she said.
But here the story takes a strange twist.
Mrs Lambert says she never suspected her team-mate Dora Ratjen was not who she appeared to be.
"She was part of the Olympic team. We all trained together and she was my roommate," she remembered.
"She never came in the shower with us, so we thought she was a little weird, but I had absolutely no idea she was actually a man."
Dora Ratjen - whose real name was Horst Ratjen - continued to compete in the high jump for another two years.
Ratjen set a new world high jump record for women in 1938 but was disqualified after a doctor discovered he had strapped up his genitals.
Mrs Lambert only learned the truth about Dora in 1968, when she read a magazine article about her former team-mate.
"When I read it I laughed like crazy. I couldn't help myself."
She says she does not know why Horst Ratjen would have carried out such an elaborate deception.
"I wrote to him some years ago, but I never got an answer. Why he did this I do not know. Maybe he was forced by the Nazis, maybe it was for his own self-esteem, I have no idea," she said.
Horst Ratjen himself said he was forced into it by the Nazis "for the sake of the honour and glory of Germany".
"For three years I lived the life of a girl. It was most dull," he is reported as saying in 1957.
He is said to have been conscripted into the army in 1938, and later worked as a waiter in Hamburg and Bremen before his death last year.
The story of Dora Ratjen has been retold recently because of the recent controversy over South African runner Caster Semenya - whose own gender has been the subject of much speculation since winning gold in the women's 800 metres at last month's World Athletics Championship.
Berlin 36 is opening at cinemas in Germany from this week.