Doug Peters / Retna Digital 1 / 2
Doug Peters / Retna Digital 1 / 2

The Proposal (out June 19) not only marks Sandra Bullock's first romantic comedy in nearly five years.

It also is the first time the actress, 44, had to shoot a nude scene.

"Sadly, my first and last nude scene got laughs, so I had to be very secure with that," she said Sunday at the film's press junket. "It was all about choreography. I mean, literally when you read it on the page, you saw it, and then you realized, 'OK, there is no way to shoot this unless you are buck naked!' Then I went, 'Go to the gym, cut out the carbs!'"

See stars who have no problem showing a little skin

The scene -- which involves a naked run-in scene with costar Ryan Reynolds -- took three days to film and over a dozen takes.

"I'm glad it made people laugh," she said. "Shooting it was odd. There are things stuck to areas that generally you don't have things [stuck to]. I mean, you have things covering [your body], but not stuck to it. And then they got unstuck, and oddly we didn't care because we were so tired."

Added Reynolds, "Yeah, at that point, shame is gone completely. The weirdest part is calling your mom nude on set: 'Hey, just checking in!'"

See photos of Ryan Reynolds and other stars sweating it out at the gym

The Proposal is Bullock's first romantic comedy since 2005's Miss Congeniality 2: Armed & Fabulous.

"I stopped doing them," she said. "They are terrible, they are bad. They are not funny, so they shouldn't be a romantic comedy and most of the time they are not romantic. So they shouldn't be called a romantic comedy. They should be called that other kind of film."

See then-and-now photos of your favorite romantic comedy stars

She said she refuses to call The Proposal a romantic comedy.

"It reminds me of the films from like the '30s and '40s where there was a landscape and a story and drama was allowed to be in there," she said. "You can't have good comedy without drama in it. And they dont generally write well for women in romantic comedies."

See stars who have no problem showing a little skin

"I love my comedy too much to bastardize it with bad romantic comedy," she went on. "So I was like, 'I'm going to find another way to work and do it in a way that I love.' So I'm not calling this a romantic comedy."