The IJF 's regulations for the Olympic Games state that no headgear can be worn .
The federation says there could be a danger to fighters if a hijab is inadvertently used for an otherwise legal strangulation grip .
The IJF 's regulations for the Olympic Games state that no headgear can be worn , and the federation says there could be a danger to fighters if a hijab is inadvertently used for an otherwise legal strangulation grip .