(Cover) - EN Showbiz - Jason Bateman struggled with one scene in his new movie, namely one where he has to have excrement in his mouth.

The Hollywood funnyman teams up with Ryan Reynolds in The Change-Up, which focuses on Ryan's playboy character accidentally swapping bodies with his straight-laced friend, played by Jason. While both loved the fact that they were making an adult comedy, Jason couldn't believe what he had to do for one scene.

"That was pudding, and it was shot out of a gun of some sort," Jason explained, when asked how they shot him having baby excrement in his mouth.

"Pudding? Where is your commitment, man?," joked Ryan immediately afterwards.

Jason also had to film a partly nude scene for the movie. While he joked that his physique on screen was the result of special effects, Ryan set the matter straight.

"They did a lot of shading for me in post-production, they kind of chopped up about 45 pounds," Jason laughed at a press conference for the movie.

Ryan then added: "Walked by his trailer one time. Actual Thigh Master action going on in there, really working the Thigh Master he was, yeah. And just like eight Shake Weights just everywhere."

The plot of The Change-Up is similar to Disney classic Freaky Friday in 1976, which was later remade with Lindsay Lohan and Jamie Lee Curtis playing the daughter and mother who swap bodies. (C) Cover Media