The 400-pound actor who plays 'The Mountain' on 'Game of Thrones' eats 10,000 calories a day and remembers 'moving huge stones' as a kid on his grandfather's farm

The 400-pound actor who plays 'The Mountain' on 'Game of Thrones' eats 10,000 calories a day and remembers 'moving huge stones' as a kid on his grandfather's farm

Hafþór Björnsson the mountain

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Hafþór Björnsson.

  • Hafþór Björnsson is the official World's Strongest Man, having won the title at the 2018 World's Strongest Man competition.
  • He's also known for his acting role as Gregor "The Mountain" Clegane on the HBO hit series "Game of Thrones."
  • Björnsson is 6'9" and weighs 400 pounds, a size he maintains by consuming up to 10,000 calories every day.
  • He told Business Insider that the secret to his strength has much to do with his diet and exercise, but even more to do with positive thinking.

2018 was a big year for Iceland's Hafþór Björnsson, who usually (and fittingly) goes by the nickname Thor.

He turned 30, got married, and won the World's Strongest Man competition, a goal he had sought for more than half a decade. He can add that to a résumé including titles such as Strongest Man in Iceland and winner of the Arnold Strongman Classic. And there's his acting role as Gregor "The Mountain" Clegane on the HBO hit series "Game of Thrones."

At six feet nine inches tall, Björnsson was always a big guy. But he didn't bulk up to 400 pounds of largely muscle through genes alone. He became the strongest man currently walking the planet through years of hard work, disciplined diet and exercise, and a positive attitude.


Realizing he had a 'gift for strength'

Björnsson told us that his participation in sports started with playing basketball when he was 12 years old. But he also spent a lot of time on his grandfather's farm, where he said he stayed active by "moving huge stones and rocks." By 16, he was at his full height, and by 19, he said, he realized he "had a gift for strength."

A recurring ankle injury that ended Björnsson's budding basketball career at age 20 would lead him to make the most of that gift, as he soon began entering strongman competitions.

When preparing for a strongman event, his training consists of a varied regimen of exercise and physical therapy sessions, helping him maintain strength while avoiding the injuries so easy to experience when a person works with hundreds of pounds of weight (or even a thousand-plus pounds, in some cases).

"I train with heavyweights five times a week. I'm in the gym so often," he said. "But there's also a lot of other stuff I do outside of the gym. I do a lot of hot and cold treatments to make sure I stay injury-free, and so I can also train more often."

Eating up to 10,000 calories a day

Hafþór Björnsson

Steven John/Business Insider

The Mountain with the author.


When we sat down with him to ask how he stays strong and in shape, the food containers stacked beside the couch indicated that diet was definitely a part of the picture.

"Diet is very important to stay in shape, to stay strong. So I'm very consistent with my meals. I eat six meals every single day," he said. "I eat mostly steak, rice, carrots, with some peppers, sometimes chicken. I eat so much, really. And definitely the hardest part of being in these competitions really is the diet."

Björnsson said that he eats up to 10,000 calories each day to be able to maintain the shape and strength necessary for competitions.

"There's a lot of eating, if you want to stay the best," he said. "I have to eat every two hours, I have to fuel my body. And there's a lot of timing, prepping meals, when I eat them. I think sometimes, 'Is this worth it?' I'm always eating, and I'm never hungry. I'm always eating and working out."

Read more: I tried intermittent fasting for a month - and I saw 7 life-changing results


The power of positivity

Becoming the World's Strongest Man goes beyond the approximately 10,000 calories Bjornsson consumes daily and the hours spent in the gym. It's also largely a mental game.

"I don't have a least favorite exercise, I don't believe in thinking about that, about least favorites," he said, when asked to name one. "I don't like to think that way. You have to have your mind positive towards everything in life, and I try to be very positive. To be good at everything, you have to be positive towards it. I train and I work very hard toward my weaknesses, and I have any weaknesses, I work even harder to make them my strength."

But does The Mountain have a favorite exercise?

"My favorite exercise is the deadlift, definitely that one," he said.

That comes as no surprise, as in the spring of 2018 he set a deadlift world record by lifting 1,041 pounds.