And she made a big impression on the judges - placing fourth out of nine competitors in her division and walking home with a trophy.
"My dad works on cars, and he shows his cars for people to judge and look at," said Loy prior to the competition. "So, I consider my body my vehicle that I'm showcasing and getting at detailed up for the weekend."
Since November, Loy – a 22-year-old nursing and phlebotomy student at Scottsdale Community College – has embraced a rigorous diet and training regimen.
"It just feels really great to be in shape," she said.
Loy hits the gym six days a week, giving her one day of rest.
The results are big, even though Loy is actually quite small.
"I'm four feet tall; 72 pounds," she said.
Loy was born with hypochondroplasia, a type of dwarfism that gives her a proportional physique.
"It's pretty much like an average height body, shrunk down into a smaller package," she explained.
Loy's coach, Gordon Beecher of Team GB Fitness, modified her training to fit her size and structure.
"She looks incredible," he said of Loy, who he calls his tiny titan. "I'm the architect for her program. But she's the one who put in all the work."
Loy's family, friends and her coach were at the event to cheer her on.
"Amanda was definitely the fan favorite tonight," said Beecher. "When she walked onto the stage, the auditorium erupted with cheers. People chanted her name."
Loy said she hopes to inspire people of all shapes and sizes.
"It doesn't matter what you look like or who you are," she said. "If you want to be fit and be the best you can be, it just takes dedication."
Copyright 2014 CBS 5 (KPHO Broadcasting Corporation). All rights reserved.
BRADENTON BEACH, FL (WFLX) - People are outraged after a Florida couple was caught having sex on a public beach Sunday afternoon in front of dozens of people including children. Bradenton Beach policeMore >>
People are outraged after a Florida couple was caught having sex on a public beach Sunday afternoon in front of dozens of people including children.More >>