Michelle Trachtenberg

Once upon a time, the term ``Ice Princess’’ would have been considered an insult. But Michelle Trachtenberg literally is an ice princess in the Disney film of the same name, opening Friday.

Trachtenberg plays aspiring Olympic skater Casey Carlyle and had hardly ever skated before the role. For the teen actress who grew up on camera as Dawn Summers in the ``Buffy the Vampire Slayer’’ series, that meant months of hard work.

Sure, Trachtenberg and Hayden Panettiere, who plays her rival, are doubled at times.

``But I personally trained for eight months for this movie,’’ Trachtenberg told The Herald last week. ``I was lucky to get a head start. I was attached to the picture before they got a director.’’

With a personal trainer and coach, she skated five hours a day, five days a week and took ballet classes every other day.

``I’d always loved to watch ice skating, only I didn’t know how intense it was,’’ she said.

Once filming began, her regimen intensified.

``It was seven days a week, filming during the week with choreography for seven hours on weekends, and sometimes 20-hour days on the set.’’

Trachtenberg sounded like a typical teen when she admitted, ``They had a whole bunch of trainers and nutritionists, but I didn’t listen. I stuck to chocolate and cheese.’’

No matter how demanding a role might be, Trachtenberg wouldn’t have it any other way. Acting is a passion for this 19-year-old, who has been working professionally since she was 3. ``And I’m a workaholic,’’ she said.

At the center of ``Ice Princess’’ are two mothers who each want to live vicariously through their daughters. Joan Cusack plays Casey’s feminist-minded single mom who dreams of seeing her only daughter succeed as a Harvard physics scholarship student. ``Sex and the City’’ veteran Kim Cattrall plays a former tough-as-nails Olympic skater turned coach and is the driving force behind her daughter’s skating ambitions.

``It’s the core of the story, that struggle between child and parent when the parent has hopes and dreams for the child and think they know best, and the child wants to go off and follow her dream,’’ Trachtenberg said. ``Where my mom in the film is pushing her daughter to Harvard, all I want to do is ice skating - and that’s the real heartfelt center.’’

Trachtenberg sees no parallels to her own life. But how does a tyke go into showbiz on her own?

``I was a rather outspoken 3-year-old,’’ she said. ``I saw a commercial where a little girl was brushing Barbie’s hair and I said, `That’s what I want - I want to brush Barbie’s hair!’ And my mom was, `OK, if that’s what you want to do.’ She got a manager who had seen kids in New York - that’s where I was living. I was sent out for my first audition, and I got my first commercial and have been acting ever since. I never had a stage mom, and I think that’s why I have longevity and am still doing it: It was always my dream and my passion. The second you stop having fun and stop loving it, you should get out of the business.’’

Another reason Trachtenberg has lasted is that she is picky. In May she co-stars in punk director Gregg Araki’s ``Mysterious Skin’’ as a gay hustler’s enduring but platonic love. Last season on ``Six Feet Under,’’ she showed her range as Celeste, ``a fabulously bitchy pop diva that I did for four episodes while training for `Ice Princess.’ It was the most fun I ever had.’’

For Trachtenberg, that gift of knowing what she wants and doesn’t want means that she’s comfortable growing up but not overly eager to do so.

``Growing up on national television wasn’t strange at all,’’ she said. ``It was actually kind of comfortable. I was on `Buffy’ between 14 and 17, and you adjust. One day you realize you need a bra here and there, and it’s scary if you have a pimple and worry about the camera catching it, but everyone has to grow up a certain way, and that’s just the way I did it.’’