She had to "practice" breathing in her corset before flaunting her incredible figure in a latex Thierry Mugler dress at the Met Gala on Monday night, according to Vogue.
And while trolls attacked Kim's incredibly slim and "fake" waist online, her personal trainer was quick to defend the reality star in a since-deleted Instagram story posted shortly after fashion's biggest night of the year.
The Daily Mail reports Melissa Alcanta posted a lengthy response to critics, writing that her client is "dedicated" and 'works her a** off' six days per week' to achieve her famous physique.
"To make things clear, 1. This dress is corseted BUT 2. Kim trains her a** off 6 days a f***ing week, she wakes up early af and is dedicated," she wrote online.
"3. . I paved the road for her but SHE did the work! I love compliments either way. MOST IMPORTANTLY I don't give a s*** about your opinions on her body if you think she fake or not!"
Melissa is regularly seen training with Kim at her home gym as the Keeping Up With The Kardashians' star updates her fans on her workouts.
"I see her every morning, I see her train and I see her sweat and I see all the work she does outside of the gym and THAT is commendable!"
She revealed that her nude Thierry Mugler gown included a Mr. Pearl "proper corset" and took "about eight months" to create.
"This is the first time in 20 years Mr. Mugler has designed for the House of Mugler. So to come and design this gown for me is such an honor," she told Vogue on the pink carpet. "This is about eight months in the making … He envisioned me this California girl stepping out of the ocean, wet, dripping."