It can be assumed that she started lifting weights and making herself muscular to probably survive the post-apocalypse and get revenge for the murder of her dad. Prior to the launch of The Last Of Part 2, the extremely muscular physique of Abby did lead people to assume that she was transgender.

How is Abby so buff?

Abby, a new character introduced in The Last of Us Part 2, does not fit the mold. Her face is anchored by a square jaw, which gives her visage a wider look — at least, compared to the heart-shaped face that defines most women in games. Perhaps most notably, Abby is buff.

Is Abby a man last of us?

As a female gamer, Abby's physicality is a rare treat. ... Some gamers do have valid criticisms of the character, who is partially controversial because she takes focus from Ellie, who stole the show in the first game.