The rumour first came to public prominence in 2008 when a Russian newspaper, owned by billionaire oligarch Alexander Lebedev, quoted a source as insisting the story was true.
Mr Lebedev shut the newspaper down soon afterwards claiming it had not been a commercial success though many suspected the real reason was to appease an angry Mr Putin.
The rumours later escalated when bloggers claimed Miss Kabayeva had subsequently given birth to Mr Putin's love child. Mr Putin has angrily claimed that there is "not one word of truth" in any of the allegations, while Miss Kabayeva's spokesperson has refused to discuss what she derided as "nonsense."
Mr Putin has rarely been seen in public with his wife Ludmila in recent years, citing a heavy workload. He married Ludmila, a former air hostess, in 1983, the same year as Miss Kabayeva was born.
My guess is that these type of sexual shenanigans with gymnasts young enough to be his daughter is just the type of thing the antichrist would go go go for, but of course there is no way to know at this time if Vladimir Putin, the most powerful and effective leader in the world, is actually the antichrist.
Click here for photos of Anna Kabayeva. Mmmmm hmmmm. Seems just the type the antichrist would go for.