Jessica Simpson shows off abs after 100-lbs. weight loss

The designer who posed in a sports bra and leggings, does 14,000 steps a day and full-body workouts

Jessica Simpson is celebrating her new fitness line.

The 40-year-old singer-turned-designer posted a new photo on her business account in which she also showed off her toned abs while wearing a black sports bra, which featured a keyhole in front, and high-waisted leggings. 

The mother-of-three has been on quite the lifestyle journey since welcoming her baby daughter, Birdie, last year. Simpson revealed she's lost 100 lbs. since her daughter's birth in March 2019. 

Her toned legs are to the credit of getting in 14,000 steps a day and full-body workouts, her personal trainer Harley Pasternak told E! News earlier this year.

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“We slowly ramped those up; we started really easy and slowly increased them," Pasternak said of the fitness regimen. "We started with doing a full-body workout, one set of each exercise, not really doing too much intensity per body part and gradually increasing the volume and intensity. Focusing on a few muscle groups per day. Different muscles each day of the week."

Simpson's health journey has her feeling like she did before she had kids," Pasternak said. "[She's] in control of everything and such a great attitude of not beating herself up if she doesn't eat perfectly everyday so it's a very helpful perspective."

In a previous post with the same outfit on, Simpson broke a sweat doing some poolside yoga

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″Starting the week with a warrior mindset aligned with the beauty of the sunset ✨″ the “Dukes of Hazzard” star captioned the post.

In addition to Birdie, Simpson and her husband, Eric Johnson, share kids Maxwell Drew, 8, and Ace Knute, 7.

JESSICA SIMPSON SHOWS OFF TONED LEGS IN NEW PIC

She told People magazine that she keeps in shape largely due to the fact she chases her kids around “all day every day.”

“I also have the most active husband ever,” she said. “If you marry an athlete, you got to stay on your feet.”