The actress suggested that Selina, whose alter ego is Catwoman, does not have the same identity crisis as Bruce Wayne does in relation to his Batman alter ego.
"I loved that the focus was [on] who she was as Selina, and that there wasn't a schism within her, that she didn't change when she put on the suit," Hathaway told Hitfix.
"It was kind of her uniform which she had to wear for her job."
Hathaway went on to describe a meeting with Christopher Nolan in which he suggested that she should work out in preparation for the role - not in order to look better, but to make her fight sequences look convincing.
"When I got the part, Chris had called me into his office and said, 'Okay, so there's gonna be a lot of fighting, and when we did Inception, Joseph Gordon-Levitt got in really good shape. Joe went to the gym for months so when he did his fight sequence, he did all of his own fighting. I really liked that'."
Hathaway took his advice and underwent a "complete transformation" physically for the role.
She also revealed recently that The Dark Knight Rises completed filming ten days ahead of schedule.
The Dark Knight Rises is released on July 20. Watch a new 13-minute preview below: