Gerard Butler explains his weight loss

Butler has been surfing every day for the movie "Mavericks."

Story highlights

  • "I'm prepping for a surf movie," Butler said
  • Butler is combining his daily water sports with a cardio regimen and yoga
  • "If the script was good, I would do it," Butler says of a rumored sequel to "300"

He's been getting a lot of attention for his fluctuating body mass, but Gerard Butler says his recent weight loss is easily explained.

"I'm prepping for a surf movie," Butler, 41, told PEOPLE at a "Machine Gun Preacher" screening Tuesday in New York. "So I'm surfing every day for 'Mavericks.'"

For the role of mentor to surfer Jay Moriarity, Butler is combining his daily water sports with a cardio regimen and yoga, the tanned (and toned) star told E!.

Not to worry, fans of his physique for 300 can have hope that the action star will get his 6'2" self back to that film's 197 lbs. of muscle.

"If the script was good, I would do it," Butler says of a rumored sequel -- and necessary bulk-up. "I've got to feel that there's a real reason to go there, to do a second one, because I loved the first."

Though he hasn't seen a script yet, Butler said he hopes his character, King Leonidas, is included.

"I hope that they write a great script and I hope that I love it," the actor told PEOPLE. "That was my favorite role, and it would be great to go back there and have some fun with it."

    See the full story at PEOPLE.com.