01/28/2009 at 10:00 AM EST
topped the charts – with a lot of hard work – and now she's promising to do the same in her upcoming world tour.
In an exclusive rehearsal photo posted to Spears's Web site
, Britney claps to the beat in simple, comfortable dance gear.
Jamie King, who choreographed her 2000 tour, is back on duty, and the singer, 27, looks svelte and toned in a tank top showing off her arms, and even the mom-of-two's tummy!
The arena tour, her first in five years, kicks off in New Orleans March 3 with special guests The Pussycat Dolls. – Jessica Gold HaralsonRELATED ARTICLE:
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