The singer and actress says she’s walking each day and finding healthy food substitutions
“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 PEOPLE that she tries to walk three miles a day with her husband, Eric Johnson, and kids, daughter Maxwell “Maxi” Drew, 7, and son Ace Knute, 5 — she’s also making improvements to her diet.
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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.
Simpson started posting about her postpartum recovery soon after giving birth to Birdie. In May, seven weeks after the baby was born, Simpson shared a photo that showed her struggling to touch her toes.
“Just stretching it out in my rubber corset,” she jokingly captioned the shot. “The joy of postpartum 🤗”
For more about Jessica Simpson’s life now, pick up the latest issue of PEOPLE, on newsstands Friday.
But beyond getting fit, Simpson is having a monumental year — along with Birdie’s arrival, she just announced that she’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.”