PHOTO: X Factor USA's Britney Spears Shows Off Flat Stomach In Bikini Shot

It's no wonder Britney Spears wore figure hugging dresses during the X Factor USA auditions after she showed off her super-toned body in picture posted on Twitter.

The star, who has been enjoying her time on the show alongside Simon Cowell, Demi Lovato and L.A. Reid, took to the social networking site to post the picture of her standing in a purple bikini with her sons Sean Preston and Jayden James.

Looking happy and content in the picture, the star posted the caption:

"Getting ready for some pool time! Having a blast! xxoo."

The star's holiday comes after she embarked on an auditions tour around the US for the show which is set to return to our screens in September.

Revealing that the 'Hit Me Baby One More Time' hitmaker has been taking her role on the show "really seriously", Simon told People magazine recently:

"She's not on the show to be Britney Spears on a TV show. She's actually there to prove to the world there's more to her, and she's got the ability to do this job really well. She's taken the role really seriously."

Check her out!

Britney!

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