The 27-year-old showed off his surprisingly muscular physique, revealing he's more confident in himself than ever before.
"What an incredible journey it has been!" he wrote. "Never could I have dreamed of being so lucky. And never would I have expected to have gained enough confidence to feel proud of how far I've come.
"For the first time in nearly 8 years I'm anti-depressant free, happy, fit and healthy! I owe every bit of growth to the amazing people I've met and the immense friendships I've made over the past few months."
He added that he was "making strides" towards his dream of being "a stunt man/action hero, "I'd be an absolute fool not to take advantage of the privilege I've been given, and I'm making a promise to anyone reading this that I will never take it for granted and will always unashamedly be myself. Thank you so much to all the amazing people in my life; past, present and future."
George also shared a video of himself using nunchucks alongside the photo.
Other Beauty and The Geek stars commented on the snap with Kiran Rao writing: "Woah!" along with a few fire emojis.
Alex Wojno jokingly added, "Damnnn hottie!! [Hit me up] xx so hot."
Eliza Sowada-Smith wrote, "YES GEORGE."
Sam Ready also commented, "Hot damnnnnn."
Frank Liu-Fu joked, "Did someone order Mozzarella? Cos George is shredded!"
"Loving this!" one follower wrote. "You are an amazing person and I loved your transformation! Hottest geek I've ever seen."
"This is so amazing to hear!" another said. "Can't wait to see how far you will go... Keep chasing your dreams."
"You're like a geeky version of [Tim Robards], looking good!" a third wrote.
George also added the hashtags "#fitspiration," "#mentalhealth," and "#fakegeek," something that followers noticed and questioned him on.
"Do I spy a 'fake geek' hashtag... #suss," one person wrote, while another added, "#FakeGeek?"
George's Beauty and The Geek partner Josie Werner previously defended the geek to Yahoo Lifestyle following rumours he's not a legitimate geek.
Some viewers thought George was a hired actor for the show, but Josie told us these rumours couldn't be any more untrue.
"He's actually a geek, he really is," she said. "I think I would know, I spent the most time with him.
"He actually has really geeky hobbies and interests, he's into comics, he's into martial arts. He runs this YouTube channel for Dungeons and Dragons, which is the geekiest thing I've ever heard of or seen or played in my life.
"And I could tell he was geeky too because he did lack some knowledge about talking to girls and sometimes he couldn't read me and I did have to teach him about confidence. It's not like he knew what he was doing the whole time."
The 21-year-old student admitted that George had told her that he studied acting, but said that it's just a hobby and "not his main source of income".
"It's also kind of sad to see people hating on him because he's an actor. So what if he is? It did not phase me. I know the real George. George is a geek.
"It's a jealousy thing because obviously he is an attractive geek, but he can't help his genes. People will find anything to try and make someone look bad."
George and Josie shocked in the finale when they performed a particularly risque Magic Mike dance.
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