The actor spoke with ET at a special pet adoption event and fan screening of ‘Arthur the King’ in Los Angeles on Monday.

In Mark Wahlberg’s inspiring new adventure drama Arthur the King, the actor stars as an adventure racer who inadvertently befriends a stray dog during a race, which accompanies him and his team for over 400 miles across the Dominican Republic.

Wahlberg made an appearance at a special fan screening at the AMC Century City 15, which served as a pet adoption event, on Monday, and spoke with ET’s Kevin Frazier about shooting the challenging film — which was made even more grueling by an injury he sustained during shooting.

Wahlberg explained that, because the film is based on a true story, “You want to pay attention to the small stuff and you want to look the part.”

This meant a lot of prep and a lot of training to get ready for the kind of racing that really goes on during these excursions.

“Unfortunately, I tore my meniscus the first day, so all my training went out the window,” said Wahlberg, referring to the piece of cartilage that serves as a cushion or buffer between the thigh bone and the shin bone. “Then it’s basically just about getting through it.”

“So I got to understand the suffering a little bit more than I wanted to,” Wahlberg added.

According to the actor, the injury literally occurred during the very first day of shooting, as they were filming the second scene of the day. He went to a doctor immediately and was warned that not pausing production and healing could lead to serious injury — but Wahlberg felt obligated to work through the pain.

“I just felt like, you know, it took a long time to get the movie off the ground and we were in the middle of COVID, and if I had shut it down, I don’t know if we would’ve got it up and running again,” he recalled

. “So I just kind of toughed it out and I found different ways of getting through.”

In fact, it wasn’t just the injury that was hard for the action star. As Wahlberg explained, “I did a lot of things that I didn’t want to do. The first was walking out of my trailer in spandex.”

“I thought I would never put on a superhero suit or spandex, and I put it on and I had to shave my legs.

What little hair I had on my legs I had to shave off,” Wahlberg revealed, referring to the Lycra bodysuits the racers wear under their gear. “It still hasn’t come back.”

In the movie, Wahlberg and his racing team — played by Simu Liu and Nathalie Emmanuel — bike, kayak, run and zipline across 435 miles of rugged terrain.

At one point, Bear Grylls makes a cameo as himself, and Wahlberg was asked if he’d ever be interested in going on a survivalist adventure with the famous outdoorsman.

“If I get permission from my wife, yes,” Wahlberg said of his wife of 14 years, Rhea Durham, with whom he shares four children.

Wahlberg explained that he even got scared during filming that his wife might get mad he went on the zipline because of how dangerous it is.

“She doesn’t think I need to be doing things that are too extreme,” he said. “I mean, I’m not doing any Tom Cruise type of stuff. But I do enough where it’s like, ‘Yeah, you don’t want to put yourself in harm’s way.'”