Even though Vin Diesel’s character Groot only says three words during Guardians of the Galaxy, Vin Diesel didn’t only record the three words one time. In an interview on the red carpet of the Guardians of the Galaxy world premiere, Vin Diesel revealed that he said “I am Groot” over a thousand times in doing his voice work for the role.

“I was really lucky, because I had a director, who is willing to indulge and wanted to really capture all the nuances of this character. What we know about Groot is that he’s got a wooden larynx so although he’s saying other things, other than “I am Groot,” all the novice ears or someone oblivious to his nuances of his speech can hear is “I am Groot.” It sounds like he’s just repeating his name. Because of that, when I came into the recording room, there was a fifty page document that on the left hand side it said “I am Groot,” and on the right hand side, it would have a paragraph or a sentence explaining what he was really meaning or what he was really trying to say. And so when you have that level of detail, when you have a director that committed, when you have studio so hellbent on creating such a great CGI character, I feel like I’m coming into a team…a winning team already. And all I have to do is spend a week there in the ADR booth breathing life into it,” said Vin Diesel.

Guardians of the Galaxy is scheduled to be released in movie theaters on August 1, 2014.