Jessica Simpson's Personal Trainer Reveals Exactly How She Lost 100 Pounds Six Months Postpartum

The mom of three, who welcomed her most recent child, Birdie Mae, in March says that she's "so proud" to feel like herself again.

That's because she weighed in at 240 pounds and had a goal of losing 100 pounds in six months.

To ensure everything was safe, Pasternak put together a plan that worked in coordination with Jessica's doctor.

"It had to be more than just getting back from her baby weight, but how do I keep whatever I am doing now forever," he said.

"That's why we are not a big fan of doing any extreme diet or radical forms of exercise."

She just had a baby at that point, so they didn't want to move too fast.

She got a break while she recovered from having the baby.

However, after that, it was time for Jess to hit the streets. Pasternak started her off on a more achievable 6,000 steps a day.

In general, though, she would eat three meals a day, along with two snacks.

Each meal consisted heavily of lean proteins and lots of veggies.

While Jess was working up a sweat, Harley was putting his brain to work.

He created Sweetkick, which is a mint that helps curb sugar cravings. Um, I'll take 12, thanks.

Sounds delish!

And instead of "cheat days," Jessica would have "cheat meals."

He never intended to "rob" Jess of her favorite things, but to make slow changes that incorporated healthier proteins and veggies.

"You don't have to have all of your indulges in one day. It tends to be a little extreme if you do that," Pasternak said.

This meant having her go on family walks and having her multitask TV and phone calls while on the treadmill.

They didn't want her doing anything "too difficult, painful, hard or arduous."

She would unplug from technology one hour before bed.

"So many people undervalue the importance of sleep in weightless and weight management," Pasternak explained.

"We slowly ramped those up; we started really easy and slowly increased them," he explained.

"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."

To meet those step goals Harley set for her, Jessica started adding family walks to her daily routine.

The whole gang would head out and work up a sweat while hitting those 6,000 and 14,000 step goals.

He said that Simpson had a great attitude during the whole process, despite having to check in daily.

For example, he tracked what she ate, her step count, and got screenshots from her Fitbit.

Daily emails helped ensure that Jessica kept Harley up to date on everything involving her get healthy journey.

Since she was at home, Jessica could take care of business and her help at the same time.

She walked on a treadmill while watching TV or answering calls.

He's now helped her lose the baby weight with all of her kids!

As a result, she trusts him and the process.

"We were kind of just getting in shape between kids and now it was sort of ok, I want to look fierce again and look great, confident and energized and I want to do it in a sustainable way. That was her main goal."

"She is feeling like she did before she had kid. In control of everything and such a great attitude of not beating herself up if she doesn't eat perfectly every day so it's a very helpful perspective."

Queen of being healthy and posing next to private jets!

She's working with Macy's on her fashion line, she's releasing a book next year with Harper Collins, and she appears regularly on the Home Shopping Network.

That's one busy mama!