The Thor: Love and Thunder trailer revealed a buff new look for Natalie Portman’s MCU character. As the Mighty Thor, Natalie Portman’s Jane Foster was seen sporting some muscular biceps in the final shot of the trailer. This clip provided the first official look of Portman in-costume as the MCU’s Mighty Thor.

Having been absent from the MCU since 2013’s Thor: The Dark World, Portman’s Jane Foster is about to make her long-awaited return to the movies in Taika Waititi’s Thor: Love and Thunder. However, her role in the movie won’t be at all similar to what it was before. Jane will go from Thor’s human, non-powered love interest to a new incarnation of the God of Thunder and the next owner of Mjolnir. How exactly the movie would pull it off, how it would her interpret her Mighty Thor origin from Marvel Comics, and how her transformation would translate to the big screen were among the biggest questions ahead of the trailer.

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Natalie Portman’s muscled arms in the Thor: Love and Thunder trailer prove that the actress has made some notable changes to her physique for the role. How she obtained her new look was discussed in an interview with Vanity Fair. Portman said she worked with a trainer named Naomi Pendergast for four months before the shoot. During this time, she consumed protein shakes and did a great deal of weight training that she wasn’t accustomed to before the movie. According to Portman, her Thor 4 workout consisted of a lot of “agility work” and “strength work”. The details of these exercises haven’t been disclosed, but other comments from the actress were indicative of just how intense they were. Portman previously described being “super tired” after her Thor 4 workouts.

Natalie Portman as Jane Foster

The amount of training Portman had to endure for her Thor: Love and Thunder role isn’t at all unexpected, considering the workout routines that other Marvel actors had to do to play their respective MCU characters. Chris Hemsworth, Chris Evans, Chris Pratt, and more have all had to go through this process. And given how important it is that the MCU’s Mighty Thor comes across as a physically imposing female warrior and someone who can be perceived as an equal to Hemsworth’s character, it makes sense for Marvel to embrace a totally new, buff look for the MCU’s Jane Foster in Thor 4.

Portman’s physical transformation for the movie is sure to be reflected by how much the character has evolved since her last MCU appearance in Thor: The Dark World. Presumably as a consequence of events that have taken place offscreen, Jane will somehow reach a point where she’ll become worthy of Mjolnir and all the power that comes with it. In the comics, Jane suffered from cancer before getting her hands on the hammer. How she overcame this life-changing challenge and became an Avenger was a testament to her strength, which is an element of her character that is sure to be vital to her Thor: Love and Thunder role.

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