Chris Hemsworth said that getting even more ripped for "Thor: Love and Thunder" was challenging and took a toll on him.
"Each time I've played the character and put the muscle on and out the size on, and then lost it for something else and played another character, there's muscle memory, and I used to say it sort of got easier each time," Hemsworth said in the latest installment of Marvel's behind-the-scenes documentary called "Assembled," released on Thursday on Disney+.
He continued: "This was particularly hard. I think because the target weight we aimed for was quite a ways above where I'd been before."
The Australian actor's physique has become larger and more muscular with each appearance in the Marvel Cinematic Universe (MCU).
Hemsworth has portrayed the God of Thunder since the first standalone "Thor" movie was released in 2011. He's since reprised the role for "Thor" sequels and "Avengers" films, in addition to voice work for season one of "Loki" and "What If...?"
He's set to return again as Thor in a yet-to-be-announced project, as indicated by the ending of "Love and Thunder."
For "Love and Thunder," Hemsworth said that he spent 12 months at home, "just training and sort of puppeteering the body" and mixing up his workout routine with swimming or martial arts.
"It was a really fun exploration, but I don't know that I wanna get that big again," he said in the "Assembled" documentary.
"It was just exhausting," Hemsworth said. "I don't know, maybe I'm getting old, but things just started to hurt more."
The actor previously opened up about his training for the fourth "Thor" film in an interview with USA Today.
Hemsworth said that he got larger than ever for the movie and credited it to "boredom" brought on by the COVID lockdown.
"It was train, eat, train, eat. Nothing else to do," he explained. "Then I turned up for the film bigger than I've ever been."
The "Extraction" star also said that his wife Elsa Pataky, who has a cameo in the movie, wasn't a big fan of his more muscular body and called it "too much.
"There are a lot of my male friends who are like, 'Yeah!' but a lot of female friends and family are like, 'Yuck,'" he said.