Lift more weights, find more mates
By Meg Sullivan
Published Jul 9, 2007 10:21 AM
Women don't just like men with muscles — they go for them.
Men who are more muscular than average are much more likely to have short-term affairs and multiple sex partners than their scrawnier peers, according to new UCLA research published in the August issue of the Personality and Social Psychology Bulletin.
"If you're trying to figure out why men — especially young men — spend so much time at the gym, here's your answer," said David Frederick, lead author and a UCLA doctoral candidate in psychology. "The stereotype is that men work out to compete with each other, but our research suggests that pumping iron is a way for men to enhance their attractiveness to women."
The series of studies, conducted by Frederick and co-author Martie Haselton, a UCLA associate professor of communication studies and psychology, is the first published research to quantify an association between men's muscularity and their success in the sack. The four-year project also scientifically quantified for the first time women's perceptions of the importance of muscularity in selecting short- and long-term partners.
Women put a premium on attractiveness
"A lot of mate-selection research focuses on what men find attractive," Haselton said. "This shows women are putting a premium on attractiveness. Women care about muscularity when they choose sex partners."
Frederick and Haselton lead a team that photographed 99 male undergraduates. A panel of independent judges rated the young men on a nine-point scale, with "1" being much less muscular than average and "9" being much more muscular than average. The researchers then asked the men about their sexual histories.
When compared with their less-muscular peers, young men who were more muscular than average were twice as likely to have had more than three sex partners in their lives.
In another study, Frederick and Haselton asked 120 undergraduate males to rate their own physiques on the same scale and then asked them about their sexual histories.
Musclemen had more brief flings, one-night stands
The self-identified muscular men had not only had more sexual partners than their less burly peers, but they were twice as likely to have had brief flings or one-night stands with women. The difference in the number of sexual partners reported by the men who were more muscular than average was also notable: They reported having had an average of four partners, compared with an average of 1.5 partners for men who reported average or below-average muscularity.
In a similar study, Frederick and Haselton asked 60 undergraduate males an additional question: How many affairs had they had with women who already had a boyfriend at the time of the affair? Muscularity mattered here as well. The more muscular individuals were twice as likely as their less well-built peers to have hooked up with someone else's sweetheart.