Carrie Underwood is turning up the heat and it’s not even summer yet…

The 33-year-old Grammy-winning country star and mother of one posted on herInstagram page Friday a sexy selfie in which she showcases her rock-hard abs in a floral, double-strap, sports bra-like bikini inside a pool. It is one of several new swimsuits from her CALIA fitness apparel collection, available for purchase atDicks’ Sporting Goods.

“I’m so proud to be able to work with @dickssportinggoods to create a line of swimwear that makes me feel so good! Adorable and athletic…and covers everything I want covered! @caliabycarrie #staythepath #summeriscoming #vegas,” she wrote.

Underwood keeps fit with the help of a personal trainer, Erin Oprea. MORE…