Captioned "Models in training @SInow sequel #happymemorialdayboys #wetryhard #having fun," Rimes, 31, and two sexy pals created a lighthearted remake of the 2014 Sports Illustrated Swimsuit Issue photoshoot, which stars models Chrissy Teigen, Lily Aldridge and Nina Agdal in the original.
As usual, the country singer evidently felt proud of her impressive figure after an extreme exercise session with L.A. dance trainer Ilyse Baker earlier in the day.
"Workouts done!" she tweeted five hours before the snapshot was posted. "Every inch of me is drenched!! @ilysebaker time for sun & a bikini!"
It was a day of working out and chilling out for the soon-to-be reality star, who spent Sunday, May 25 at the 2014 Indy 500 with husband Eddie Cibrian, 40, where Rimes sang the national anthem.
“The horns they played right before the NA moved me to tears. I was crying the first few lines of the song," she tweeted of her emotional performance.
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