Carrie Underwood just had a baby a few months ago, but by the way she's showing off her new threads from her own Calia activewear line, you would never be able to tell.

E! went behind the scenes of Underwood's photoshoot for the new line (available fall 2015) to get the scoop on the inspiration behind the clothes, plus what it's like for Underwood getting back into fitness after having baby Isaiah.

"It's been interesting getting back into my fitness routine ever since I had Isaiah. It's the most wonderful thing in the entire world, but of course there's so much that comes along with having a baby — your schedule completely changes," the "Little Toy Guns" singer explains. "I have to kind of be ready to workout whenever I possibly can."

In the behind-the-scenes clip, the 32-year-old is shown effortlessly doing pushups and pull-ups, giving inspiration to those who are interested in purchasing their own Calia clothes. Clearly, Underwood is more than ready to get back on the stage during CMA Music Fest this week. You can catch her perform during the CMT Music Awards on Wednesday (June 10) night or at LP Field in Nashville on Saturday (June 13).

"Fitness to me — I've been vocal about it over the years — is a lifestyle," she says. "I just love how I feel when I feel good about myself. There's definitely a lot of me in the Calia line."

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