Twilight star Kristen Stewart has revealed that even though she plays the part of a rock star on screen, she is nowhere close to being one in real life.

Stewart, 19, who portrays Joan Jett in her new film The Runaways, really admires the 70s musician’s rocking swagger.

“If I had that drive... It could never be fun for me to be a rock star because I’m not one,” the Mirror quoted her as telling US talk show hosts Regis Philbin and Kelly Ripa.

The actress also revealed that she had to study Joan carefully to ensure she does her justice on the big screen.

“Yeah [I felt some pressure], especially for the performances because she has such a distinct voice,” she said.

“She is on fire. She stares the audience down. I’ve never seen anything like it and you don’t know you can do it until you do it for the first time,” she added.