Britney Spears' new album, Circus, has topped the charts. Now she's working out like a madwoman to deliver a world tour worthy of such widespread hype.

In a photo series on her website, Britney shakes it to the beat in "simple, comfortable dance gear." Sure it's comfortable - there's barely any clothing on her...

The singer, 27, looks svelte and toned in a tank top showing off her arms, abs and stomach. This tour is going to flat-out kick ass. Or at least be really expensive.

Just pray she doesn't ask this guy to be a backup dancer.

"The Circus Starring Britney Spears," her first tour in five years, kicks off in Louisiana March 3. Click to enlarge more Britney Spears pictures of her rehearsing: