The 33-year-old actor - who strips off in new movie `No Strings Attached`, in which he stars alongside Natalie Portman - admitted he enjoys "having it out" because he feels natural when he doesn`t have his clothes on.
He told BANG Showbiz: "I don`t know why but I like having it out. I like being naked! We all come into the world this way. There`s very little you can do about it, you are who you are. Doing the scene, it doesn`t matter. It`s infinitely awkward. You have 40 strangers standing around.
"I think it`s less awkward for guys than girls because the crew tends to be slightly more masculine. And, you know, mine doesn`t look that much different from yours. Whenever I`m doing something like that, when it`s a sexual scene I get out of myself by trying to make sure the other person`s OK."
While the hunk - who is married to actress Demi Moore - is comfortable with nudity, he admits he wasn`t so cool around girls when he was in High School.
He confessed: "I was a bit of a fumbler. Yeah, I didn`t really have a girlfriend until I was a senior in High School. I was fairly nervous about the whole thing. I didn`t manage very well."