Iranian women are subject to a strict Islamic dress code, which requires that they wear a headscarf and loose-fitting clothes that cover the body. "Nude" can refer to any woman who violates this law.
The woman has not been identified, but local media speculated that she is well-known bodybuilder Shirin Nobahari, who has an Instagram account with 69,000 followers under the name "Shirin Muscleking."
Nobahari is one of two female Iranian bodybuilders who took part in an international bodybuilding contest in September.
According to Iran's Mizan news agency, the woman was jailed after failing to post bail of two million rials ($62).
"One of the female bodybuilders who recently published nude photographs on social networks has been arrested," Mizan announced.
While Iranian women are permitted to compete in sporting events internationally, they must adhere to the dress code. For example, female athletes have to wear tracksuits with long sleeves, and swimmers have to wear full bodysuits and head coverings.
In 2013 female swimmer Elham Asghari set a new Iranian record when she swam 20km of the Caspian Sea in nine hours, wearing a full hijab. However, according to France24, her record was not recognized by the Iranian authorities on the grounds that her swimming costume was too revealing.
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