As Kit Harington gets older, he's increasingly moved away from the bulkier physique that defined some of his earlier roles.
At 39, he's just been announced as Nicholas Hoult's replacement to play the fame-obsessed, fraudulent celebrity wizard Gilderoy Lockhart in the second season of the Harry Potter TV series – a role that doesn't exactly demand a Jon Snow-style physical transformation.
But that won't stop Harington from consistently getting himself to the gym. These days, looking a certain way is secondary to what training does for his head.
Training to Stay Mentally Sharp
'If I don’t go to the gym at least three times a week, the sad boy in the corner comes back,' Harington told Mr Porter earlier this year. 'In all seriousness, if I don’t go to the gym at least three times a week – and I do yoga twice a week – my head goes really fucking weird. I get very depressed.'
That's not to say Harington doesn't care what he looks like. He's previously made conscious changes to his physique for roles, including losing weight to play Sir Henry Muck in Industry.
On that occasion, he purposely cut weight because he wanted his character to look like he was on 'smack'.
'In the end, I just looked ripped,' he added. 'I quite like looking less bulky now. As I get older, I think it looks better. So, I’ve swapped protein shakes for intermittent fasting instead.'
Another Industry scene required Harington to step naked out of a swimming pool, providing a rather different reason to tweak his training.
'That was my own work,' Harington told GQ. 'I go to the gym for my head anyway. But when I knew I was getting my bum out, I was like, "OK, you're on the squats this week."'
Building Jon Snow and Milo
Harington first started building serious strength for Game of Thrones, where playing Jon Snow required him to spend long days carrying around roughly 10kg of coats and furs.
He took his physique considerably further for the 2014 film Pompeii, spending five weeks hammering the weights to add muscle while getting extremely lean for his role as Milo.
'I’m not a 6ft 3in guy who can bulk up and just look like an absolute unit, a tank. My body type has a tiny bit of stockiness to it but it’s really quite wiry, so for Pompeii that was the sort of look I had to go for – "prison fit", like Robert De Niro in Cape Fear,' Harington told MH.
Why Harington Keeps Coming Back to the Gym
But the transformations only tell part of the story. Harington appears to genuinely enjoy training, even when there isn't a role requiring him to look a certain way.
In early 2026, he went viral after Connecticut gym Iron House Fitness shared the story of a month-long period he spent training there in 2019. Harington had recently left rehab for alcoholism when he was referred to the gym and initially arrived with one simple goal: learning to box.
'Kit Harington got referred to our gym,' the gym wrote. 'Then he trained 28 days straight. Not for a role. Not because someone told him to. Because something clicked.
'He came in with a simple goal: he wanted to box. I used to box, so we started there. Nothing fancy. Just mitts and movement. At first, he was on a two-days-a-week rhythm. The schedule most people pick when they're feeling things out. Then something changed. Two days turned into every day. We mixed boxing with CrossFit-style conditioning, and he loved the energy of it. You could feel the momentum building.'
Nearly two decades after first getting into shape for Jon Snow, the motivation may have changed. The habit clearly hasn't.
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Ryan is a Senior Writer at Men’s Health UK with a passion for storytelling, health and fitness. Having graduated from Cardiff University in 2020, and later obtaining his NCTJ qualification, Ryan started his career as a Trainee News Writer for sports titles Golf Monthly, Cycling Weekly and Rugby World before progressing to Staff Writer and subsequently Senior Writer with football magazine FourFourTwo.
During his two-and-a-half years there he wrote news stories for the website and features for the magazine, while he also interviewed names such as Les Ferdinand, Ally McCoist, Jamie Redknapp and Antonio Rudiger, among many others. His standout memory, though, came when getting the opportunity to speak to then-Plymouth Argyle manager Steven Schumacher as the club won League One in 2023.
Having grown up a keen footballer and playing for his boyhood side until the age of 16, Ryan got the opportunity to represent Northern Ireland national futsal team eight times, scoring three goals against England, Scotland and Gibraltar. Now past his peak, Ryan prefers to mix weightlifting with running – he achieved a marathon PB of 3:31:49 at Manchester in April 2025, but credits the heat for failing to get below the coveted 3:30 mark…
You can follow Ryan on Instagram @ryan.dabbs or on X @ryandabbs_
