From PEOPLE Magazine Click to enlarge
BEFORE
She lost 30 lbs.!

KayCee Stroh wants to make one thing clear: She has always been proud of being "bigger"—even when the other girls in dance class would "look at me like, 'Ha! You're a dancer?'," or when her recital costumes were so small that her mother "had to buy two of the shirts and sew them together," Stroh recalls.

But at 19, Stroh developed a blood clot in her left calf (the result of a previously undiagnosed clotting disorder, which, if left untreated, can be fatal) and spent three months on bed rest—gaining nearly 40 lbs. For the first time, she felt awkward in her body, especially at the 2005 audition for High School Musical. "I was so uncomfortable walking into that room—everyone else was in bra tops and bike shorts," says the 5'2" Stroh, whose weight peaked at 210 lbs. "I thought, 'Maybe this one is just for practice.'"

As most of the American teenage population is aware, Stroh scored the part—and has become a fan favorite as HSM's "pop-and-lock" girl. "If Hollywood had more incredible girls like her as an example, the world would have some wonderful people to look up to," says her close friend and HSM costar Corbin Bleu.

Despite this triumph, however, Stroh longed to get back to a size she felt comfortable at. Now, just in time for the Aug. 14 premiere of High School Musical 2, the 23-year-old Salt Lake City native is almost there. After three months of doing 50 minutes of cardio followed by crunches six days a week and eating lots of chicken, vegetables and salad, Stroh has trimmed down from a size 20 to a 14—one step away from her size 12 goal. "I don't want people to think that I'm giving in to the pressures of Hollywood—I truly believe that sexy doesn't have a waist size," says Stroh, who models for the plus-size clothier Torrid. "I just want to be healthier and happier."

For Stroh's diet tips and a video of her photo shoot go to PEOPLE.COM/KAYCEE