Chris Hemsworth's muscles steal the show in brother Luke's Instagram photo

Chris Hemsworth may have bid his chiselled physique adieu for his role in In the Heart of the Sea, but on a recent outing to lunch with his brother Luke, his bulging bicep stole the show. Taking to Instagram, the actor's sibling noted his tank top-clad brother's muscles and caused a full-on social media meltdown.

Hey @chrishemsworth do you even lift bro? @lukemun @emerysurfboards

A photo posted by hemsworthluke (@hemsworthluke) on

Chris Hemsworth is back to his muscular figure.

"Hey @chrishemsworth do you even lift bro?" Luke quipped in the caption as his brother showed off his muscular bicep while the pair hung out with friends.

This marks an incredible transformation for Chris, who just months ago was unrecognizable after having lost a dramatic amount of weight for the action film. The star alarmed fans when he posted a photo of his skinny body, but quickly reassured them that it was a temporary look.

Read More: 5 reasons why Chris Hemsworth is MCM-worthy every day

"Just tried a new diet-training program called 'Lost at Sea,' " he quipped in the caption accompanying the Instagram snap, referencing the upcoming drama in which he plays a first mate left shipwrecked with his crew in the ocean after a whale attacks their boat. "Wouldn't recommend it … #IntheHeartoftheSea."

Just tried a new diet/training program called "Lost At Sea". Wouldn't recommend it.. #IntheHeartoftheSea @zocothebodypro

A photo posted by Chris Hemsworth (@chrishemsworth) on

Chris shocked fans with his dramatic weight loss for In the Heart of the Sea.

At the time of filming, the Avengers: Age of Ultron star revealed he found the weight-loss process "pretty uncomfortable" but quipped that he was comforted because he was joined by the other cast members in the gruelling routine.

"We have to shoot the really skinny stuff where we drop down to five, six, 700 calories a day, a good three or four weeks," he told Entertainment Tonight. "And it's going to be pretty uncomfortable, but we'll be together in our misery."

Chris, who is married to Spanish model and actress Elsa Pataky confessed that he didn't find the dieting lifestyle particularly appealing because he often felt hungry. "I spend more time thinking about food than anything else at the moment," he said.

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