Among some pretty intense training regimes, the Twilight star said he even counted the number of sips of water he was having in order to look his best in front of the camera for his starring role.
Of course, it’s worth pointing out here that we’re definitely not recommending this, and you should drink as much water as you like.
In fact, drinking plenty of water is something that we’d strongly suggest.
Also, wear sunscreen.
Kids, ask your da.
Anyway, back to R-Patz.
The star revealed he only had a few short months to get into shape for his role as the Caped Crusader and knew he needed to be looking tip-top for the part.
So, he embarked on a vigorous training regime and even kept strict tabs on how much fluid he was taking on.
He told PEOPLE: "I had about three months before the movie started, and then you're working out before and after work all the time.
"You just cut down and cut down and cut down before the couple of scenes with your shirt off, and you're counting sips of water."
The 35-year-old also told the publication about how knowing that he’d have to appear with his top off was a huge motivating factor for him.
He joked: "Oh yeah. Shame is my biggest motivator, 100 percent."
Well, we hope that he’s joking, at the very least.
In keeping with most of the other iterations of Batman – campy Adam West version aside – the film is quite dark, which Pattinson also claimed made his skin react to the lack of light.
He explained: “I was really, really, really dead afterwards. I looked at a photo of myself from April and I looked green.
“The nature of the shoot was so kind of insular, always shooting at night, and I felt very much alone.
"You’re not really allowed out of the studio with the suit on, so I barely knew what was going on at all outside.”
Also, it took a psychological toll on him too. "I have to really, really feel like I’ve hit rock bottom [to get into character]," he told GQ.
"Where right up until the moment I have to perform it’s, ‘Wow, I’m the most empty piece of s***’.
"You have to feel the pain. And suddenly it’s like God gives you a little treat, ‘Here’s an idea you’ve never thought of before’."
Anyway, if all of this bleak chat has you chomping at the bit to see the final results, you can see it tomorrow in cinemas across the UK.
Batman movies aren’t supposed to be heartwarming anyway.
Featured Image Credit: Warner Bros./Alamy
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