“High School Musical”'s KayCee Stroh Says Fans Wrote to Disney Channel, ‘Shaming’ Them for Casting Someone ‘Unhealthy’ (Exclusive)

KayCee Stroh played Martha Cox in the 'High School Musical' franchise

KayCee Stroh never felt she fit the mold of a typical dancer. From the time she started dancing at the age of 2, the Salt Lake City native remembers hearing from people she admired — friends, mentors and even dance competition owners — that her talent was overshadowed by the fact that she didn’t have the "ideal" dancer body. "You'll never make it in this industry," she recalls being told.

So, when 19-year-old Stroh was cast by Kenny Ortega as High School Musical's Martha Cox, the pop-and-lock girl in High School Musical, she felt, for the first time in her life, truly seen.

"My whole life I was a bigger, muscular, curvy girl," the actress tells PEOPLE.

"The one thing I thought would always hold me back was the very thing that made me who I am, and it made me stand out that day," she adds. "It all made sense to me. It was like my whole life came into focus — I was supposed to be this way, I was made this way for a reason, and I needed to change the world's perspective on this."

Related: 'High School Musical' Cast: Where Are They Now?

But years later, Stroh, now 40, reflects on her role as one of the trailblazers for plus-size women in film and admits that it wasn’t as easy as it seemed; she often "felt very alone" in her journey. One tough moment, she says, occurred shortly after being cast as Martha, a role she landed through a former choreographer who happened to be working on the film.

Speaking to PEOPLE, Stroh remembers when she learned someone had written into Disney Channel, criticizing them for casting "someone as unhealthy as myself," claiming she was a bad role model. (Disney did not answer PEOPLE's request for comment.)

"If they only had taken the time to get to know me and realize that I grew up dancing five hours a day, and that wasn’t at all the situation," Stroh says, adding how she'd dance so much as a child she remembers taking naps on the studio floor and listening to the sound of tap shoes.

"It was so devastating to see how people just prejudge others based on something as shallow as their outer appearance while they're here on this earth," she continues, adding that just before HSM, she'd had knee surgery and dealt with a blood clot, which led to a 50-lb. weight gain. "I'm glad it happened when I was young and fresh in the industry because I really learned quickly to build empathy for others."

"Healed people don't hurt people, and I hope those people can someday find happiness and heal their inner trauma, or the generational body trauma that was passed on to them," she adds. "I really just look at it like, 'I'm sorry for you.' I hope you find happiness and realize someday that there's so much more to life than that."

Stroh, now a wife and mother of two young girls, adds how, as a child, the only time she saw larger bodies represented on screen, they were either the butt of a joke or heavily typecast. She explains that one of the reasons she was excited to play the supporting role of Martha — a student, school cheerleader and avid dancer — was because, throughout the film, her body was never portrayed as "a joke" or discussed in a negative light.

Instead, the focus was on her love for learning and dancing. She even notes how recently her character was referenced during an episode of High School Musical: The Musical: The Series, where it was mentioned she'd gone on to become a renowned choreographer.

"It really sent such a strong and beautiful message to every little girl out there who doesn't fit the mold," she says. "I feel honored that I had the chance to be a part of that and to be the vessel to tell that story, especially the way Martha changes from the first film to the third and really finds her confidence."

"She goes from being shy and timid to being head cheerleader," she continues. "It's everything that I've dreamed of my whole life, getting that message out to the world. And it was like this role was just literally perfect for me to do so."

Related: High School Musical's KayCee Stroh on the Costar Who 'Saved' Her — and Which Other Castmates She Still Texts (Exclusive)

To this day, Stroh says people still recognize her as Martha wherever she goes — whether it's at grocery stores or drive-throughs. She finds it amusing, especially since, at the time she was cast, she had no idea the film would become as successful as it did.

But as an actress, she says that being part of a classic movie is the ultimate dream. "What an incredible thing to love what you do and then have others love it too. That's really rewarding and really rare," she says. "I'm honored ... it just keeps living on."

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