Updated

When we see actors playing comic-book heroes, we assume their feats of strength are the product of clever editing and CGI. And sometimes that's the case.

Other times it's not, as "Arrow" star Katie Cassidy can attest.

"My character is an attorney, and also just recently, she has evolved into a superhero. My other alter-ego, I guess you can say, is the Black Canary," says Cassidy, who stars as the DC heroine on CW's hit series.

But as Cassidy explains, changing into an alter-ego is a lot harder than simply throwing on a costume — not that she's complaining.

"Turning into the Black Canary has been so awesome, and so much fun, and [so much] fight training," she says. "It's just a dream come true."

She's not kidding about the training, either. According to Cassidy, she works with a weight-lifting trainer five days a week, and supplements that with yoga and spinning whenever she can. "It's about just constantly mixing it up," she says of her regimen.

"Also, aside from that, this year I started martial arts," adds Cassidy. "I've also been working with the tonfa, which is basically the nightstick that Black Canary uses — which has been really fun." (In other words, criminals in Starling City wouldn't want to run into Black Canary or Katie Cassidy in a dark alleyway.)

Watch the video above for more of Cassidy's exclusive interview with FNM, and be sure to tune in for new episodes of "Arrow" airing Wednesday nights on the CW.