How do you lose half of your body fat and gain abs of steel in just five months?

Ask the staff of marketing firm Viceroy Creative. Four members of the team took on an intense diet and exercise regimen to prepare for a major photo shoot with AdWeek— in the nude.

Within five months, David Moritz, Aaron Bearce, Raegan Gillette, and Gabrielle Rein had transformed their bodies into those of statuesque models. How did they do it? Was it starvation? Surgery? Nope. “It was a combination of diet and exercise,” says Aaron.

All four went on specialized diets and followed intensive training regimens that both added muscle and trimmed their body fat levels. But along with magazine-worthy physiques, they each obtained the tools they needed to maintain a strong, healthy body in the long term.

Following specialized diets created by Body University in San Diego, the four colleagues ate six meals a day, focused mainly on protein, green vegetables like broccoli and asparagus, rice, fish, and lean meats such as chicken and turkey.

“The hardest part for me was the diet piece, by far,” says Aaron. His meal plan allowed for 2,000 calories per day, including 283 grams of protein, 120 grams of carbohydrate, and 12 grams of sugar. “I was never hungry, but I definitely had cravings for things that weren’t on the diet. Basically, sugary things and carbs!”

What helped, he says, was that each diet included a reward system to ward off cravings. “I’m a sweets person,” says Aaron. “There was no real sugar allowed, but at the end of the night I was allowed to eat a Pop-Tart.”

Reagan and Gabrielle were on similar diets, taking in about 200 calories per meal. Raegan would start each day with a cup of gluten-free Rice Chex, unsweetened almond milk, and half an apple. For lunch, it was three ounces of grilled chicken, with a cup of spinach, and half an avocado.

While they were already active, fit people, the time leading up to the photo shoot required a level of intensity they’d never expected. They worked with Equinox trainers five days per week, doing at least an hour of weight training followed by cardio.

“I’m the kind of person who goes to the gym two or three times a week, but not to such intense levels, just maintenance,” says Aaron. Adds Raegan, “I was a bit of a runner, but definitely not a weight lifter! I did not work out to that intensity.”

For the first four months, they focused on boosting their cardiovascular health, strengthening their muscles, and speeding up their metabolism. “First we had to get in shape for the training. After just a few months, every exercise was done in a triple or quadruple combination without rest,” says David.

“I would work out with [my trainer] in the morning, and by the end of the day I couldn’t even lift my arms over my head. And then I’d have to go back the next morning, even though I still couldn’t lift them!” recalls Raegan. “I just had to keep my eye on the prize.”

Gabrielle was on the same program, even though she’d recently had a baby. Her regimen focused on rebuilding her abdominal wall and strengthening her core so that she could take on weight lifting and full-body workouts.

“The experience really opened my eyes to the levels that you can target a specific muscle group in a single day,” says Raegan.

When it comes to showing off a fit body, it’s not all about the exercise. The final four weeks saw the group amp up their regimen to give their bodies definition.

The men reduced their intake to about 1,700 calories per day (compared to a typical 2,200 to 2,400). The women consumed 1,300 calories (compared to 1,800 to 2,000).

By the time they were ready to strip for the camera, all of them had reduced their body fat by at least a third. Gabrielle and David reduced their body fat by almost half, to 16.5 and 6 percent, respectively. Aaron and Reagan reduced theirs to 9 and 20.5 percent, respectively.

Compare those figures to the national average of 25 to 31 percent for women and 18 to 24 percent for men.

All four say their body fat has since increased to more sustainable levels. But what hasn’t changed is their dedication to leading healthier, more active lives.

Aaron works out four days per week, and sees the same trainer often. Raegan works out six days a week. “The experience really captured a need to work out and stay healthy. It makes me feel good,” she says.

If boosting your fitness levels and shedding a few pounds is something you aspire to do, the team has some advice:

1. Be open

“Tell people about it and put some social capital into it so that you feel like you can’t get out of it,” says David. “It would really help to jump-start the training and learn how to get that fire and determination necessary to keep going, and eventually smooth it out to a lifestyle change.”

2. Be social

“My advice to people who have fitness goals is to make it social, to do it with friends,” says Raegan. “With all of us in the same boat, there was a real level of camaraderie.”

“And a little competition,” adds Aaron.

3. Be aware

“The biggest learning for me came from the diet, and understanding what it takes to build and maintain muscle, and what kinds of food you need to eat,” says Aaron.

4. Be good to yourself

“Have a very specific goal in mind when you start, and reward yourself. If it’s 25 pounds in 4 months, have that goal in mind and reward yourself for getting there,” says Aaron.

“Everyone needs motivation,” he adds. “Ours was getting naked in a publicly available document… That’s motivation!”

Getting a six-pack in five months took lots of hard work and discipline. The Viceroy Creative team set a specific goal and then adjusted their diet and exercise routine.

They recommend a diet high in lean protein combined with strength training and cardio workouts to boost fitness and get toned.