Bullock said she has suffered setbacks but sees them as a learning experience.
"I've handled adversity and I'm sure there's a lot more to come," Bullock said.
"I haven't always acted or reacted in a way that made me proud but I didn't make that same mistake twice and I think that's what I love about adversity is that it always reminds me of what's really valuable in life."
She said her performance in Mexican director Alfonso Cuaron's "Gravity", which required that she spend time in an LED-lighted box to help produce the film's stunning special effects, had been demanding physically and mentally.
"It wasn't a walk in the park for anyone involved, especially Alfonso," Bullock said.
"I mean the immense pressure that he was under, technicians were under, no one knew if this would work until the day I got into the first contraption.
"Even then they didn't know if it would work technically or if the actor in the contraption could pull it off, it was a great unknown every single day because we were all in the same boat.
"Everyone was in it together. There was no one-upmanship on this film."
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