Armstrong believes agents discriminated against her because of her plus-size body.
In a video for The Scene, Armstrong explained that most dancers are expected to be tall and thin. Her plus-size body made her feel sidelined by the dance community.
"Growing up in a dance environment, I did feel like my body was a negative [thing]," she said. "I couldn't fit [into] costumes, and my costume was always different from everyone else's."
In fact, studies show many dancers suffer from poor body image — and oftentimes disordered eating — due to the pressures of their profession. Another plus-size dancer, Whitney Way, failed out of dance class before deciding to start her own body-acceptance campaign.
That's why Armstrong started her own dance troupe, the Pretty Big Movement.
The troupe, which specializes in hip-hop, jazz, and ethnic dance, serves as a "platform for women with voluptuous curves in mainstream media," according to the Pretty Big Movement website. Armstrong founded the troupe with two plus-size dancers she met at an audition for Full Figured Fashion Week.
The group currently boasts seven members, ranging from ages 24 to 32. They've danced in a flash mob alongside Salt-N-Pepa for Lane Bryant's "I'm No Angel" campaign, and competed in "America's Got Talent" Season 10. They even have their own reality show in the works.
Sonia Allen, one of the group's oldest members, said the troupe feeds her passion for dance.
"We all share this being thicker than a Snicker, but we can dance," she told The New York Daily News. "It's not that we are big and can dance. It's [that] we can dance and are big."
Armstrong said creating the group has made her more confident in her own body.
"You would never get me in a unitard five years ago. Absolutely not," Armstrong told The Scene. "But now I'm like, 'I'll put on a unitard, so what?'"
She said instilling that same spirit in other women is the thrust of the movement.
"When they see us perform, I want them to be inspired," she said. "...I want them to leave like, 'I was blown away.'"