Kate Upton Calls Out Body Shamers While Admitting She Used to Think Baseball Players Were 'Kind of Fat'

Glamour Magazine

Kate Upton is calling out body shamers once again.

Rocking a striped cropped top with a matching striped skirt, the 24-year-old blond beauty glows on one of the three covers for Glamour magazine's October issue (which also features Emily Ratajkowski and Joan Smalls), and in her accompanying interview, she opens up about the haters who criticize her atypical model figure.

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Upton reveals that at the beginning of her career, people used to tell her to lose weight "All. The. Time."

"At first I tried to diet to become their image, but eventually I realized that it wasn’t realistic -- that this is just the shape of my body," she explains. "So I had to block them out. I think that the people who are the loudest about wanting to change you are the people with the least amount of vision and creativity."

Upton was born in St. Joseph, Michigan, in 1992, but moved to Melbourne, Florida, with her family when she was seven years old. Growing up in the Sunshine State, she was constantly in a bathing suit, which taught her a lot about body confidence at a young age.

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"I knew nothing about fashion growing up, because in Florida, you just wear bikinis and flip-flops," she dishes. "But kids can be cruel, and they used to make fun of me for having long legs and bushy eyebrows. My mom would flip through magazines and say, 'Look, all these models have that too.' I decided I wanted to be a model."

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"Where I grew up, it was considered a great thing to have a curvy body to fill out a bathing suit. For that to be a negative [thing] was so confusing to me," she adds. "And besides, when I started working, I was booked constantly, mostly for catalog work. So when people were saying, 'Oh, she doesn’t have the right look for a model,' I thought, 'Then why am I working every single day?' There are so many different directions you can take in the modeling industry, so many ways to be successful."

Flash forward to present day, and Upton says she still receives cruel comments regularly -- especially on Instagram.

"In the beginning it was so hurtful," she admits. "But I have to say, the other day I was reading some negative comments, and I was thinking they were really funny. So I guess they don’t [bother me] anymore."

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Recently, she's been posting a lot of workout videos to the app, crediting trainer Ben Bruno for her toned figure. "He's fun and hard-core," she says of their time in the gym together.

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"A couple of years ago, there was a switch for me," Upton continues. "I used to work out to have my hips be a certain size. Now I do it for myself, because I want to be strong. I want to have energy. In my mind I feel like I can beat someone up -- I really want to be able to do it! Oh, and I want a nice butt, and if it's a quarter inch bigger than the modeling-world standard, that's fine."

Luckily, Upton's fiancé, MLB pro Justin Verlander, helps keep her fitness goals on track daily.

"This is probably bad to say, but I’m going to say it anyway: I always thought that baseball players were kind of fat and not athletic," she confesses. "I was really surprised by how athletic Justin was. I wanted to learn tennis, and he goes out and he’s never played before and just beats me. I’m thinking, 'This is the worst. Who invited you?'"

The 33-year-old Detroit Tigers pitcher popped the question earlier this year with a stunning custom-designed engagement ring, which Upton debuted on the Met Gala red carpet in May. At the time, her rep confirmed that the couple was keeping their nuptials private, and had yet to set a date.

WATCH: Kate Upton Engaged to Justin Verlander -- See Her Stunning Ring!

"We're really happy right now and just continuing being happy," Upton told ET.

Hear more in the video below.