Sandra Bullockis praising her costarChanning Tatumfor his “disciplined” approach to staying in shape.Bullock, 57, appeared onThe Late Late ShowWednesday with Tatum, 41, where they chatted with hostJames Cordenabout their upcoming filmThe Lost City,including how Tatum trained for his nude scene.Corden said his guest appeared to be in “peak Tatum physique,” adding that when he embraced theMagic Mikestar, it felt like “hugging a tree.“Paramount PicturesTatum explained that he was in “heavy rehearsals” forMagic Mike 3, keeping up a workout routine and a strict diet. Bullock said she saw the same discipline on set ofThe Lost City.“He’s really disciplined,” she said of Tatum’s ability to stick to his training regimen when preparing for a film. She added, “He has incredible willpower.“Never miss a story — sign up forPEOPLE’s free daily newsletterto stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human-interest stories.Tatum chimed in to explain, “That’s just fear. That’s just fear and ego because you have to be butt naked onscreen.“When Bullock pushed back, saying she never had to be naked onscreen, Tatum replied, “That’s because you produced it and wrote this thing.“After the two shared a laugh with Corden, Bullock admitted, “That’s correct.“Bullock previously shared some behind-the-scenes stories about her new movie during an appearance onThe Late Show with Stephen Colbertearlier this month. The actress told host Stephen Colbert about what it was like tofilm Tatum’s nude scene, in which she helps his character remove leeches from his body.RELATED VIDEO:Channing TatumTeases “Super Bowl of Stripping” inMagic Mike’s Last DanceIn the scene, she was “full-on, face-to-face, with the landscape,” Bullock said, referring to Tatum’s nude body. “I had to spend some time down there. Just making sure uh, no leeches. I had a lot to say to it.“When Colbert asked whether Bullock’s character seemed surprised in the scene because Tatum was “generously endowed,” she replied, “Let’s just say that I honestly didn’t notice.““When you are down there and you have two pages of dialogue, if you are looking directly at it, you will get nothing done,” she said. “I looked at his left thigh. I had to look down where it might be, but I focused more on the left inner thigh.“The Lost Cityalso starsDaniel Radcliffe,Patti Harrison, Da’Vine Joy Randolph andBrad Pitt. The film opens in theaters March 25.

Sandra Bullockis praising her costarChanning Tatumfor his “disciplined” approach to staying in shape.

Bullock, 57, appeared onThe Late Late ShowWednesday with Tatum, 41, where they chatted with hostJames Cordenabout their upcoming filmThe Lost City,including how Tatum trained for his nude scene.

Corden said his guest appeared to be in “peak Tatum physique,” adding that when he embraced theMagic Mikestar, it felt like “hugging a tree.”

Paramount Pictures

The Lost City first look

Tatum explained that he was in “heavy rehearsals” forMagic Mike 3, keeping up a workout routine and a strict diet. Bullock said she saw the same discipline on set ofThe Lost City.

“He’s really disciplined,” she said of Tatum’s ability to stick to his training regimen when preparing for a film. She added, “He has incredible willpower.”

Never miss a story — sign up forPEOPLE’s free daily newsletterto stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human-interest stories.

Tatum chimed in to explain, “That’s just fear. That’s just fear and ego because you have to be butt naked onscreen.”

When Bullock pushed back, saying she never had to be naked onscreen, Tatum replied, “That’s because you produced it and wrote this thing.”

After the two shared a laugh with Corden, Bullock admitted, “That’s correct.”

Bullock previously shared some behind-the-scenes stories about her new movie during an appearance onThe Late Show with Stephen Colbertearlier this month. The actress told host Stephen Colbert about what it was like tofilm Tatum’s nude scene, in which she helps his character remove leeches from his body.

RELATED VIDEO:Channing TatumTeases “Super Bowl of Stripping” inMagic Mike’s Last Dance

In the scene, she was “full-on, face-to-face, with the landscape,” Bullock said, referring to Tatum’s nude body. “I had to spend some time down there. Just making sure uh, no leeches. I had a lot to say to it.”

When Colbert asked whether Bullock’s character seemed surprised in the scene because Tatum was “generously endowed,” she replied, “Let’s just say that I honestly didn’t notice.”

“When you are down there and you have two pages of dialogue, if you are looking directly at it, you will get nothing done,” she said. “I looked at his left thigh. I had to look down where it might be, but I focused more on the left inner thigh.”

The Lost Cityalso starsDaniel Radcliffe,Patti Harrison, Da’Vine Joy Randolph andBrad Pitt. The film opens in theaters March 25.

source: people.com