Jessica Simpson looks fit as she models a bikini for her summer collection.

Jessica Simpson has served as her own model while promoting her summer Jessica Simpson collection on social media.

The Dukes Of Hazzard actress, 41, looked stunning when she was seen in a striped bikini while out in the mountains in images shared on social media.

The blonde beauty has kept off the 100 pounds she lost after welcoming her third child, Birdie Mae Johnson, two years ago.

Top Model: Jessica Simpson has served as her own model as she promotes her summer Jessica Simpson collection on social media

Top Model: Jessica Simpson has served as her own model as she promotes her summer Jessica Simpson collection on social media

Dreamy in the desert: The 41-year-old Dukes Of Hazzard actress looked stunning when she was seen in a striped bikini while out in the mountains in images shared on social media

Dreamy in the desert: The 41-year-old Dukes Of Hazzard actress looked stunning when she was seen in a striped bikini while out in the mountains in images shared on social media

Dreamy in the desert: The 41-year-old Dukes Of Hazzard actress looked stunning when she was seen in a striped bikini while out in the mountains in images shared on social media

The A Public Affair singer wore her blonde hair in loose curls while heavily made up with bronze tones for her outdoor shoot.

She added a straw hat, a sheer floral blanket and platform shoes while she was in the hills of Southern California.

‘Bohemian breezes usher in a wonderful weekend! ☀️✌️ Tap to order summer stock from @jessicasimpson’s sold-out Annalyn platforms on the site now!’ is on her company’s Instagram page.

Slender star: The blonde beauty has kept off the 100 pounds she lost after welcoming her third child, Birdie Mae Johnson two years ago

Slender star: The blonde beauty has kept off the 100 pounds she lost after welcoming her third child, Birdie Mae Johnson two years ago

Slender star: The blonde beauty has kept off the 100 pounds she lost after welcoming her third child, Birdie Mae Johnson two years ago

Glam Goddess: The singer from A Public Affair wore her blonde hair in loose curls while heavily made up with bronze tones for her outdoor shoot

Glam Goddess: The singer from A Public Affair wore her blonde hair in loose curls while heavily made up with bronze tones for her outdoor shoot

Glam Goddess: The singer from A Public Affair wore her blonde hair in loose curls while heavily made up with bronze tones for her outdoor shoot

In 2019, the author’s trainer explained how she lost all the weight after her third child.

Trainer Harley Pasternak said that after she “tip the scales at 240 lbs” postpartum, she’s worked hard to create a sustainable plan for her health and wellness goals.

“It had to be more than just coming back from her baby weight, but how can I keep doing what I’m doing now forever,” he explained to AND! News.

He added: “That’s why we’re not big fans of extreme diets or radical forms of exercise.”

Smart cookie: Her clothing and accessories line are bestsellers

Smart cookie: Her clothing and accessories line are bestsellers

Smart cookie: Her clothing and accessories line are bestsellers

She felt good: She added a straw hat and a translucent floral blanket, as well as platform shoes while she was in the hills of Southern California.

She felt good: She added a straw hat and a translucent floral blanket, as well as platform shoes while she was in the hills of Southern California.

She felt good: She added a straw hat and a translucent floral blanket, as well as platform shoes while she was in the hills of Southern California.

Boho babe: 'Bohemian breezes usher in a wonderful weekend!  ☀️✌️ Tap to order summer stock from @jessicasimpson's sold-out Annalyn platforms on the site now!'  it was on her company's Instagram page

Boho babe: 'Bohemian breezes usher in a wonderful weekend!  ☀️✌️ Tap to order summer stock from @jessicasimpson's sold-out Annalyn platforms on the site now!'  it was on her company's Instagram page

Boho babe: ‘Bohemian breezes usher in a wonderful weekend! ☀️✌️ Tap to order summer stock from @jessicasimpson’s sold-out Annalyn platforms on the site now!’ it was on her company’s Instagram page

Pasternak spoke to DailyMail.com about using the five daily behaviors he previously promoted in his book titled: 5 pounds with the mother of three.

“We made sure Jessica’s Fitbit read at least 12,000 steps every day before going to bed, made sure she got at least seven hours of good sleep a night, [and] disconnect from technology for at least an hour a day,” said Harley.

The other two principles included that Jessica followed a diet consisting of three meals and two snacks, all of which prioritized protein and fiber.

Her Path: In 2019, the author's trainer explained how she lost all the weight after her third child.  Trainer Harley Pasternak said after tipping the scales at 240 lbs postpartum, she's been working hard to create a sustainable plan for her health and wellness goals

Her Path: In 2019, the author's trainer explained how she lost all the weight after her third child.  Trainer Harley Pasternak said after tipping the scales at 240 lbs postpartum, she's been working hard to create a sustainable plan for her health and wellness goals

Her Path: In 2019, the author’s trainer explained how she lost all the weight after her third child. Trainer Harley Pasternak said after tipping the scales at 240 lbs postpartum, she’s been working hard to create a sustainable plan for her health and wellness goals

His take: “It was supposed to be more than just coming back from her baby weight, but how am I going to keep up with everything I’m doing now,” he explained to E! News . He added: ‘That’s why we’re not big fans of extreme diets or radical forms of exercise’

Snacks are okay: The other two principles were that Jessica ate a diet consisting of three meals and two snacks, all of which prioritized protein and fiber

Snacks are okay: The other two principles were that Jessica ate a diet consisting of three meals and two snacks, all of which prioritized protein and fiber

Snacks are okay: The other two principles were that Jessica ate a diet consisting of three meals and two snacks, all of which prioritized protein and fiber

She would also do short resistance workouts every other day. Harley said losing 100 pounds in six months wasn’t the specific goal for Jessica as she embarked on her postpartum health journey

“The goal was the process,” he said. “There was never a specific number on the scale that anyone had in mind. It was, “Do the work, and the rest will follow.”‘

When asked why walking was prioritized, Harley explained that it was “the ultimate fat-burning exercise.”

“Training with resistance exercises is the best way to tone, tone and tone,” continued Harley. “But to lose weight, nothing beats walking. Both are essential to achieve the goals you want.’

For Jessica’s diet, she usually ate a breakfast of scrambled eggs (one whole egg and three egg whites) with a bowl of blackberries. Then she ate a salad with grilled chicken for lunch and grilled fish and vegetables for dinner.

Getting in shape: Jessica was able to prioritize her fitness and health goals after pregnancy by focusing on walking 12,000 steps a day and following a balanced diet.  Pictured is Jessica in September 2019

Getting in shape: Jessica was able to prioritize her fitness and health goals after pregnancy by focusing on walking 12,000 steps a day and following a balanced diet.  Pictured is Jessica in September 2019

Jessica in October 2018 when she was pregnant

Jessica in October 2018 when she was pregnant

Getting in shape: Jessica, pictured left in September 2019 and right in October 2018

Snacks were a handful of almonds or green beans topped with Parmesan.

“She never starved herself and focused on getting all the things she needed to thrive,” said Harley.

Her most recent mirror selfie received a number of rave reviews, including one from James Decker.

Another follower said: ‘You look ABSOLUTELY INCREDIBLE! Keep it up, beautiful!’

Family-of-five: She is a mother to Maxwell Drew Johnson, nine, Ace Knute Johnson, seven, and Birdie Mae, two

Family-of-five: She is a mother to Maxwell Drew Johnson, nine, Ace Knute Johnson, seven, and Birdie Mae, two

Family-of-five: She is a mother to Maxwell Drew Johnson, nine, Ace Knute Johnson, seven, and Birdie Mae, two

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