McAdams, 35, played the obnoxious but amazing Regina George in the film. There were stories that Lohan felt intimidated by her but 'The Notebook' star dismissed the notion, reported E!Online.
"If anything, I was in awe of her talent. I looked at her as this experienced actor, and she had great comedic timing, so natural. It's just funny to hear that because you never know what people are thinking. We all try to act like we've got it together," McAdams said.
"I remember standing backstage, dressed like a mechanic. I had a pink bikini on underneath, grease on my face, and I just remember breathing deep and thinking, 'Oh, my God, I have to go out there and do this striptease, as a man... As a woman. How did I get here?' It was probably one of the scariest moments I've had in my career. It stretched me in ways I could have never imagined. Literally," she added.