Millions of men spend endless hours tweaking their bodies in the gym.
But flexing certain personality traits may be a more effective way of attracting sexual partners, say researchers.
A new study from Australia states that four distinct qualities are directly linked to "sexual frequency and reproductive success" among men. They include being outgoing, nice, emotionally stable and conscientious.
However, the same features do not work as well for women.
Researchers from the Queensland University of Technology analyzed 2,998 heterosexual men and 1,480 heterosexual women as part of the 2016 Australian Sex Survey.
They found that being extroverted, pleasant, emotionally stable, and highly conscientious results in greater sexual frequency for the former.
In addition, the highest extroversion was associated with men who had more children.
However, eyebrow results – published in the journal Personality and Individual Differences – differed considerably for women.
They were only sexually successful when they were more extroverted, while being "nicer" was associated with having more children.
The findings suggest that certain "combinations" of personality traits give men an advantage when seeking partners.
"Throughout history, competitive advantages have helped men and women achieve greater success in their occupation, sport, artistic endeavors, their ability to acquire and secure resources, and ultimately their survival," says Dr. Stephen Whyte, who led the study.
"However, little is known about the advantages or disadvantages that personality traits provide in relation to sexual activity and the success of the offspring.
"Science does not have a firm understanding of how personality traits influence human reproductive behavior and mating, particularly if certain personality types are favored by males or females.
"Our findings suggest that greater variation in male traits and their particular combinations may provide an advantage for them when it comes to sex and reproduction, but this does not appear to be the case with the women we review," he said.