ABC News May 6, 2015

Beyonce's Trainer on How She Got That Met Gala Body

Rabbani and Solimene Photography/Getty Images
Beyonce arrives at "China: Through The Looking Glass" Costume Institute Benefit Gala at the Metropolitan Museum of Art, May 4, 2015, in New York.

Beyonce's body was on full display in her jeweled peekaboo dress at Monday's Met Gala, and the singer looked fitter than ever.

To pull off such a daring display, Beyonce apparently started preparing weeks in advance.

The singer's personal trainer and the founder of 22 Days Nutrition, Marco Borges, told E! News that Beyonce did his plant-based, 22-day revolution.

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Borges called it "unique in that it's not a diet but rather a way of life, which starts with habit formation over 22 days."

He added, "With most diets, you see weight loss and then as soon as the program ends the weight slowly starts to add back up again. With The 22-Day Revolution, you'll experience weight loss, improved sleep, clear skin, increased energy, improved sex drive and more, but unlike other programs, at the completion of the 22 days the benefits continue because you walk away armed with the tools [habits] you need to continue experiencing these remarkable benefits. ... In short, the best version of you emerges."

There seems to be little doubt that we were seeing the best of Beyonce at Monday's ball. But this isn't the first time Beyonce apparently has gone vegan.

In December 2013, she and her husband, Jay Z, undertook a 22-day vegan challenge, sharing photos of their meat-free meals on Instagram.

This past February, Beyonce announced that she was teaming up with Borges to create their own 22-day meal service.

The meal plan, dubbed, “22 Days Nutrition” lets you choose meal plans with options between one to three meals per day for as many days of the week as you’d like, all delivered to your doorstep. The dishes are organic and gluten-, soy- and dairy-free, and run $9 to $16 per meal.