SLIPPERY ROCK — Several hundred people may have gathered in the Slippery Rock University Smith Student Center Ballroom to see a reality show star, but Tara Costa was there to share her formula for weight-loss success.

The first thing the “Biggest Loser” television show participant wants people to know is her success is not just about weight loss. It’s about making healthy lifestyle changes.

Costa, a “Biggest Loser” Season 7 finalist who lost 155 pounds in 18 months, shared her story when she spoke Wednesday night.

“I was the cute, chubby little girl that blossomed into the chunky teenager,” said the Long Island native and former financial manager.

“I went to New York University and worked hard to get good grades, but I didn’t understand the work/life balance,” she said.

As a result, Costa said, her weight reached 316 pounds and she reached what she called her “Aha moment” when she was denied entrance to a nightclub because of her size.

“I was tired of being the fat girl in the room,” Costa said, when later she saw a notice for “Biggest Loser” auditions.

Costa said she began working out even before reporting to the show in September 2008 because she was embarrassed to be more than 300 pounds.

Once at the “Biggest Loser” location outside Malibu, Calif., she weighed 294 pound when she began receiving treatment that helps contestants change their fitness and eating habits. Doctors, nutritionists, counselors and exercise specialists worked with Costa and other contestants to implement healthy lifestyle changes that result in weight loss.

During her 18 weeks at camp, Costa never once “fell below the yellow line,” which the show uses to oust contestants who lose the least amount of weight.

Costa won a record-setting eight challenges, the most in show history.

She credits her mental toughness for being able to withstand weeks of exercising six to 10 hours a day.

“It’s challenging at first and it takes time and effort,” said Costa, but developing the mental stamina was worth it.

She called it having GAME: goal, assess, motions and emotions.

“Set small goals. Once I physically completed them, mentally it made me stronger and builds self-confidence,” Costa said.

She returned in May 2009 for the show’s season finale. She weighed 155 pounds.

Questioned by the audience about enduring the shouting from “Biggest Loser” trainers, Costa said, “You are given an opportunity, make of it what you will. There were 500,000 applicants for 20-some spots. You have to take advantage of that.”

Four years after her stint on the show, Costa says she’s kept off 75 percent to 80 percent of the weight she lost, but it hasn’t been easy.

“Because I’m a food addict, it’s a struggle every day to make the best choice, like every other addict,” Costa said. “but unlike other addicts you have to eat three times a day.”

Costa founded The Tara Costa Inspire Change Foundation, which promotes a healthy lifestyle by encouraging Americans to embrace positive changes.

“Tara exemplifies what is possible when someone creates a vision and becomes dedicated to healthy change” said Jeff Lynn, associate professor of exercise and rehabilitative sciences at SRU and head of its wellness committee.

“We started this committee two years ago,” said Lynn. “We have moved slowly and carefully to get it off the ground.”

He said he met Costa through the nationwide Exercise is Medicine initiative.

“She goes around giving these talks. I knew it would be valuable for the community here,” said Lynn. “We could have a big event and bring awareness to the campus community.”

Student groups representing wellness programs provided healthy-lifestyle pointers from information booths outside the ballroom.

They provided information about SRU’s Exercise is Medicine initiative, yoga and Zumba classes, eating healthy snacks, practicing safe sex and pursuing spiritual wellness.

“The campus is committed to the wellness of the people on it, students and employees,” Lynn said. “This will be part of Tara Costa’s talk, understanding we have control over our behaviors.”

Lynn said Costa’s own story is an illustration of that. In addition to starting her foundation, she just received a master’s degree in physical education, has finished one ironman triathlon and is training for another.

“She’s living proof of what can happen when you take control of your behaviors,” Lynn said. “She’s a great example of what is possible. It all comes back to choices you make every day.”