Duplitzer, a silver medallist at the 2004 Games in Athens and a member of the fencing team for London 2012, said the International Olympic Committee (IOC) has sold out the Games for commercial interests.
"They're developing their own values and rules that are moving further and further from the Olympic spirit," she said in an interview with Monday's Bild newspaper. "Who doesn't like watching the flame being lit, or a child carrying a dove through the stadium, with dramatic music, with all those sentimental buttons being pushed? The sport is just a sideshow."
The 36-year-old added, "The IOC presents itself as something noble, helpful and good - then frankly they should behave like it.
“Unfortunately the opposite is true. Banks get sued now if they've lied in their brochures. The IOC sells its shiny wares, and lies until the cows come home. But no-one is interested. The world likes being taken for a ride."
Duplitzer reserved particular ire for the IOC's ban on athletes sponsoring products during the Games, while the organizing bodies benefit from huge sponsorship deals. "I think it's an outrage, and extremely unfair on the athletes," she said. "But it's not been about the athletes for a long time."
She also said the doping controls at the Olympics were a joke. "If you have a bit of money for medication, a good doctor, and a lax federation, you'll never be caught," she said.
"The doping hunters can only test for what they know. If you take a fifth generation EPO [performance enhancing drug Erythropoietin] made in some rat lab in China, you can gobble down as much of it as you like and you won't get a positive test. Only the idiots get caught."
Duplitzer also took some time to swipe at the German Olympic Sports Confederation (DOSB).
"The performances are getting worse and worse, because the system is completely broken," she said. "After these Olympics we're going to have a huge problem raising new talent. We already have a massive coach problem. Our coaches are running away, because they can earn a lot more in other countries and have better conditions."
DOSB spokesman Christian Klaue told Die Welt newspaper that there was no official reaction from the DOSB to the interview. "The interview speaks for itself," he said. "But I don't think that she will be excluded from the team because of it."
Duplitzer said she had been inundated with support after the interview's appearance. "My Facebook profile nearly exploded, and I got a lot of emails from coaches and athletes who said, 'It's great that you said something,' " she told state broadcaster ZDF on Monday.
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"No-one wants to open their mouth, because they don't want to be thrown out of the support system," she said. "And it is very difficult to question the existing structures." But she said athletes should not just be treated as people who "just hold the flag up at the Olympics a bit."