Men who hold oppressive beliefs about women and gender equality may be more likely to endorse traditional stereotypes of masculinity, which include being muscular.

Men obsessed with building muscles are significantly more likely to objectify women, be hostile toward women, and have sexist attitudes, new research finds. This link may come from their own negative body image, the scientists added.

"We have previously found that men who hold stronger oppressive beliefs are more likely to think that thinner women are attractive," study researcher Viren Swarmi, of the University of Westminster in the United Kingdom, told LiveScience in an email.

This sexism and objectification by men can lead to a more negative body image for women, can hinder women in the workplace and can even cause women to perform worse on cognitive tests.

Not only does it impact women, "but we're also arguing that those oppressive beliefs directed at women also have an impact on men's own body images, specifically their drive for muscularity," Swarmi said.

Of muscles and men

A group of 327 heterosexual British men filled out questionnaires for the study. Most were white, and 38.5 percent were single, 31.2 percent were in a dating relationship and 23.9 percent were married. (The rest fit into an "other" category.) [5 Myths About the Male Body]

The surveys gauged participants' desire for a more muscular body — for example, asking how often they think "I wish that I were more muscular" — and their attitudes toward women. Examples of items in the sexist beliefs portion of the survey included: "I feel that many times women flirt with men just to tease them or hurt them," and "Intoxication among women is worse than intoxication among men."

Those men who showed more interest in being muscular were also more likely than others to score higher on sexist beliefs, hostility toward and objectification of women.

"We think men who hold oppressive beliefs about women and gender equality are also more likely to endorse traditional stereotypes of masculinity, which includes the muscular physique," Swarmi said.

"In addition, in societies where patriarchal structures are being challenged, some men may seek to reassert their masculinity by enhancing their physiques." For example, they might react to having a female boss by beefing up at the gym.

Mass media

Though they didn't study this directly, it is possible that the sexism and concentration on attaining muscle mass are both linked to increased consumption of mass media, Swarmi said: "It's likely being driven by changes in the way the ideal male physique is portrayed in the mass media."

But that's probably not the only reason for the correlation. "It seems likely that the mass media play a role in increasing levels of drive for muscularity we see in many contemporary societies, but we were interested in broader social influences," Swarmi said, for example, changes in gender dynamics away from a male-dominated society.

"We're arguing that patriarchal attitudes and beliefs also play a role," Swarmi said. Men with ideas that the family or company should be ruled by the man may have trouble dealing with changing gender roles in the modern world. Men may use their muscles to reassert their dominance and masculinity.

The study was published May 28 in the journal Psychology of Men & Masculinity.

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