Melissa Benoist says it's hard work to be 'Supergirl'

It will be tights, flights and all kinda fights when "Supergirl" soars into National City this fall after keeping her identity and her super powers a secret for the 12 years she has been on planet Earth.

"In my everyday life, I've always been such a pacifist," says Melissa Benoist, who plays Kara Danvers aka Supergirl. "I grew up in a household full of women, and if you hit someone, it was a huge deal, even just a slap. The butt kicking is new. That's a new muscle I'm flexing, but I'd be lying if I didn't say I liked it."

CBS is taking a page from its sister CW network and entering the superhero programming competition with the fall series based on the DC Comics' character Kara Zor-El.

Benoist admits she wasn't a big comic book reader growing up, but she did enjoy sci-fi movies, including "Star Wars." Since being cast, she has rectified that and read lots of DC's The New 52 "Supergirl" series.

"When I told the producers that, they were like, "Well, this is our own universe. We're kind of creating this on our own.  Obviously, they're using a lot of the canon but I think they wanted me to really have a fresh take on it."

Benoist, who earlier this year married her "Glee" co-star Blake Jenner, has discovered that it's a long way from belting out a tune to taking down the bad guys. The physical challenges of "Supergirl" were initially daunting.

"I've had to train quite a bit," she tells FOX411. "I've been training since the pilot and before. It's challenging. It's tiring. It's a good thing, though. She's got to be really, really tough and strong to show girls and anyone that you can overcome the things that you're afraid of."

Being in shape is also essential when it comes to wiggling into her costume, which, while covering her, is still formfitting with lots of legs!

"I love that I grew up as a dancer so it feels like a leotard, a skirt and tights that I wore when I was a ballerina," she says. "What is impractical and sometimes painful is my costume has a corset. My cape is a corset, so sometimes when I'm on the wire that is constricting. Even so, I think I'm very lucky in terms of my suit, I know a lot of people have masks that sweat and don't breathe at all."

"Supergirl" will also delve into Kara's life when she is out of costume and wearing civvies, so she will have a personal life.

"[The producers tell me], 'Take away the fact that she fights aliens, what would this girl be like? What would her life look like?' We're definitely going to discover that. She has a lot of complicated relationships and things to explore. She's juggling everything."

"Supergirl" premieres on Monday, Oct. 26 on CBS.