Actors who got seriously buff for roles
Gerard Butler: '300' (2007) -
If you watch '300' on mute, it's basically just a group of ridiculously buff men jumping around in underpants and capes, and Gerard Butler is the leader of the pack!
Jake Gyllenhaal: 'Southpaw' (2015) - Jake Gyllenhaal often plays unimposing characters, but 'Southpaw' (2015) showed a completely different side to him.
Alicia Vikander: 'Tomb Raider' (2018) - Alicia Vikander inherited the role of Lara Croft from Angelina Jolie for the 2018 'Tomb Raider' remake.
John Krasinski: '13 Hours: The Secret Soldiers of Benghazi' (2016) - John Krasinski circa 2013 is a very different John Krasinski to the one who played Jim in 'The Office.'
Tom Hardy: 'Bronson' (2008) - Bronson has spent a great deal of his life in prison, so Hardy built muscle by performing exercises that can be done in a jail cell.
Emily Blunt: 'Edge of Tomorrow' (2014) - Emily Blunt had two and half months to turn herself into a warrior woman who fights extra-terrestrials with ease.
Chris Hemsworth: 'Thor' (2011) -
In 2011, Chris Hemsworth took on the role of Thor, one of the most formidable superheroes in the Marvel universe.
Bradley Cooper: 'American Sniper” (2014) - Bradley Cooper packed on 40 pounds (18 kg) of mass in 10 weeks to accurately portray Navy SEAL sniper Chris Kyle.
Linda Hamilton: 'Terminator: Dark Fate' (2019) - She undergoes a serious transformation over the decades as her character evolves and becomes tougher and stronger.
Chris Pratt: 'Guardians of the Galaxy' (2014) - Chris Pratt bulked up like crazy for his leading role in 'Guardians of the Galaxy' (2014).
Brie Larson: 'Captain Marvel' (2019) - She trained for nine months to increase her strength and gained 15 pounds (7 kg) of muscle to get into superhero shape.
Josh Brolin: 'Deadpool 2' (2018) - The guy was pushing 50 and managed to do it in 11 weeks, making it all the more impressive.
Henry Cavill: 'Man of Steel' (2013) - These days Henry Cavill is the definition of a superhero bod, but it wasn't always that way. The actor used to be teased about his weight as a kid.
Michael B. Jordan: 'Creed' (2015) - He gained 24 pounds (11 kg) of muscle over the space of a year by training two to three hours per day and eating an incredibly bland diet.