Jessica Simpson in Bathing Suit Has "Extra Passion"

Jessica Simpson is heating things up south of the border! The singer, actress, and entrepreneur steamed up social media this week with her latest post, a photo of herself in a cutout swimsuit walking on the beach in heels. “The sun is settin’ on the most romantic, sexy and well deserved (if I do day so myself) Mexican getaway with my forever lover @ericjohnsonalrighhhht. Awww I will miss this, but I will be bringin’ home a lot of extra passion for everyone and everything that is for sure Adios Cabo San Lucas,” she captioned the post. How does the 42-year-old maintain her fit physique? Read on to see 5 ways Jessica Simpson stays in shape and the photos that prove they work—and to get beach-ready yourself, don't miss these essential 30 Best-Ever Celebrity Bikini Photos!

1. Her Diet Is Healthy

Jessica followers her trainer Harley Pasternak’s Body Reset Diet, eating three healthy meals a day of protein, fiber, and fat-rich foods and two snacks of protein and fiber or protein and fat. “She’ll have foods that are very flavorable that are healthier versions of things like a tortilla soup or Tex-Mex," the celebrity fitness instructor explained to People. She is also allowed to splurge on occasion. “It’s about balancing in a way that doesn’t make it painful or too much of a departure from your life before that.”

2. She Doesn’t Focus on the Number

Pasternak explained to People that Jessica doesn’t pay attention to numbers. “I never work with scales. My work with her is more about the habits she’s created and kept up. And as a byproduct of doing these habits, she lost 100 pounds,” he said. Jess added to Today that she doesn’t weigh herself. "I have no idea how much I weigh," she said. "I just want to feel good and be able to zip my pants up. If I don't, I have another size. I have every size."

3. She Trains Hard

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Jessica makes her workout sessions with Pasternak count. She does 45-minute sessions three days a week, consisting mostly of strength and weight training exercises.

4. She Gets a Lot of Sleep

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Jessica also makes sure to get enough sleep, per the guidance of Pasternak. "So many people undervalue the importance of sleep in weight loss and weight management," he told People."Every night before she goes to bed she sends an email showing that she hit all five tasks, so she’ll go to bed feeling successful. She’s hit her step goal, she’s eaten well, she’s balanced her responsibilities — so she can go to bed with a sense of fulfillment, and that’s everything."

5. She Keeps Track of Her Steps.

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Jessica gets her steps in! She uses an activity tracker to make sure she hits her goals. When she first embarked on her weight loss journey, her goal was 6,000 steps per day, eventually building up to 14,000, per E! News. “It’s a social thing that she can do with her kids," Pasternak said.