Rumors are swirling that LeAnn Rimes got a breast augmentation, but the country crooner didn't let that ruin her Mexican beach vacation, stepping out in a teeny bikini over the holidays.

Rimes told Shape magazine's October issue that she enjoys "punching out" some of her aggression at the gym, and that method seems to be working for her as this pic of the country crooner's beach bod proves.

She told Shape that she and her now new fiancé Eddie Cibrian often hit the gym together. "He's going to kill me for saying this," she says, "but when I ask him to work out with me, he always says no. And when I ask why, he says, 'Because your workouts are too hard.'"

Rimes and "CSI: Miami" star Cibrian got engaged over the holidays.

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