Today’s strong female protagonists are overwhelmingly described as “small,” “skinny,” and “slender.” It seems literature only goes so far in its message of female empowerment, routinely granting its most kickass heroines classically masculine-levels of strength (physical or otherwise) only when cloaked within the trappings of a more delicate—and recognizable—femininity.

Since these characters are nearly always underestimated based on their size, it’s safe to assume readers are meant to see their triumphs as all the more impressive. Having a tiny heroine is an easy way to create a satisfying David and Goliath narrative—the stuff on which young-adult fiction is built. But so many stories about powerful young women employ this trope that it can’t just be written off as lazy characterization. Besides, would their arcs be any less compelling if their thighs touched, or they occasionally had to invest in a sports bra?

None of these books fawn over their leading ladies’ size, but, by default, they link being undersized with being exceptional—each of these characters is singled out as special for having more grit, skill, and/or magical prowess than most everyone around them. Divergent goes so far as to associate flab with low moral character: When Tris first meets her nemesis Jeanine, she wears a tight dress that reveals “a layer of pudge around her middle” and knees “crossed with stretch marks.” Of course the virtuous heroine is delicate and birdlike, while the unsympathetic villain has stretch marks.

There’s clearly something intriguing about strength in small packages, but only when it comes to female characters. Male leads, by contrast, are more often described using language that would typically indicate power; Tris is the “skinny girl from Abnegation,” but Four, her love interest and training instructor, has a deep voice that “rumbles” and muscles that are “taut, defined.”

Being skinny isn’t a bad thing, but it becomes an issue when so many of the strongest female characters around conform to a single body type—especially one long associated with a narrow definition of what it means to be feminine. And in more adult fare, this archetype of the delicate-looking action hero often gets twisted into a fetish disguised as girl power. (Just look at the ultra-violent Girl With the Dragon Tattoo, Sucker Punch, and virtually everything Joss Whedon has ever written.)

But this is the same double standard that we’ve been subjected to again and again; just as women are expected to be sexual but not slutty, pure but not prudish, heroines should be strong but not buff. Powerful, yet still delicate enough to be cradled by their male love interests. Mature enough to lead those around them, yet so small that people confuse them with innocent little girls.

Characters like Katniss, Tris, and Clary are rightly praised for being self-sufficient role models, and proving that female-driven stories sell books. I just hope that someday, strong female characters will actually reflect and affirm the diversity of the young readers who idolize them.

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