Jessica Simpsonis gettingher body moving again!

The singer and actress, 39, gave birth to daughterBirdie Maeon March 19, andafter a tough pregnancy— which includedsome seriously swollen ankles— Simpson is working on getting back in shape.

“I am working really hard right now,” she says. “It’s not easy at all, but I am determined to feel good. I have been doing a lot of walking — getting my steps in not only burns calories but it also helps me clear my head and get focused.”

Along with her daily steps —Simpson previously told PEOPLEthat she tries to walk three miles a day with her husband, Eric Johnson, and kids, daughterMaxwell “Maxi” Drew, 7, and sonAce Knute, 5 — she’s also making improvements to her diet.

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Jessica Simpson

The singer with her family.Jessica Simpson/Instagram

Jessica Simpson

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“I am eating healthy too — I discovered I really like cauliflower. Who knew it could be a substitute for almost anything?!” she says.

“Just stretching it out in my rubber corset,” she jokinglycaptioned the shot. “The joy of postpartum 🤗”

For Simpson’s life now, pick up the latest issue of PEOPLE, on newsstands Friday.

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people magazine cover

But beyond getting fit, Simpson is having a monumental year — along with Birdie’s arrival, she just announced thatshe’s writing a memoir— and she’s celebrating it as she hits 39 years old on July 10.

“I feel pretty good about 39!” she tells PEOPLE. “It is definitely one of those numbers that makes you think about age — last year of the 30’s and all — but on most days I feel like I have earned it.”

source: people.com