Carrie Underwood Showcases Toned Bikini Body in Sexy Selfie

She posted the photo before performing at the 2016 ACM Party for a Cause Festival

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 her Instagram 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 at Dicks' 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.

Later on Friday, Underwood headlined the ACM Women of Country Night event during the 2016 ACM Party for a Cause Festival at the Las Vegas Festival Grounds. She wore a white, sparkly, cutout fringed top over black ripped skinny jeans.

Other performers included Cam, Kelsea Ballerini, Martina McBride, Kellie Pickler, Maddie & Tae, Lauren Alaina, Kelleigh Bannen, Brandy Clark, Miranda Lambert and Jana Kramer. The event took place two days before the 2016 ACM Awards, where Underwood and most of the other artists are also set to perform.

Lambert made a surprise appearance during Underwood's set to perform "Something Bad" with her. For the finale, Alaina, Bannen, Kramer and Pickler joined Underwood onstage to perform her hit "Before He Cheats." Underwood then performed two songs for her encore—"Smoke Break" and "Something in the Water."

The event also marked an American Idol alumni get-together: Underwood won season four in 2005, Pickler placed sixth in season five in 2006 and Alaina came in second place in season 10 in 2011.

A video posted by Jana Kramer (@kramergirl) on Apr 2, 2016 at 12:42am PDT

Kramer posted on her Instagram page a video from the Friday event as well as a group photo with Underwood, Pickler, Alaina and Bannen.

"Oh ya know...just singing with @carrieunderwood!" she wrote. "Thanks for having us girls up there with you on stage!!! #girlpower @acmparty."

Thanks again to @carrieunderwood for having us girls up on stage with you tonight!!! @kelliepickler @laurenalaina @kelleighbannen @acmparty

A photo posted by Jana Kramer (@kramergirl) on Apr 2, 2016 at 1:00am PDT

 

"Oh my goodness..." Underwood said. "What an honor it was to share the stage with such beautiful, strong, talented women!"