For decades, men and women have decreed that when it comes to sex, It's not the size of the boat but the motion of the ocean.

Now a Victoria University (VU) study into penis size and body image has discovered that size does matter to men, but chiefly in relation to how they shape up compared with other men.

It's the locker room syndrome, said principal researcher and Doctor of Clinical Psychology student Annabel Chan. Men are more concerned about how their overall body size compares to the perceived male ideal than they are about how their size might impact on their sexual relations.

The study, which investigated the link between men's penis size, body image and mental health, found that men who indicated a larger-than-average penis size had higher self esteem, better general health functioning and higher overall body satisfaction than those reporting an average or below-average sized penis.

The study also revealed that men who were happy with the size of their penis were less likely to engage in online dating. Ms Chan said that because a large penis was considered a cultural ideal, the survey results were not a great surprise, but they provided fresh insight into male perceptions about their bodies.

We have relatively little data about the body image of men because most of the research in this area concentrates on women. This survey starts to correct that, she said.

Men with poorer self-esteem and higher body dissatisfaction have a preference for online dating as initially, physical attractiveness does not deliver the primary impression.

Respondents who had more internet dating behaviours tended to be younger with a higher body mass index (BMI). They also displayed dissatisfaction with their penis size, lower self-esteem and higher drive for muscularity.

The study was one of the first to look at the association between men's beliefs about their penis size, how they feel about their bodies, and psychological wellbeing. It was completed online by more than 700 men aged 18-76 from 43 countries.

Other revelations included:

  • Compared to their ideal body size, 5.8% of respondents were satisfied with their body size, 89.7% wanted to be bigger and 6.6% thought they were already bigger than the ideal.
  • But when comparing their ideal body size with their perceived ideals of others, 26.2% had the same ideals, 65.1% of them think their ideal size is smaller than the perceived ideal body size of other men, and 8.7% think their ideal size is bigger than what they perceive other men would prefer.
  • Participants who had never used Viagra were more satisfied with their penis size and had less online dating experience than those who had.
  • Overweight men have lower self esteem, higher body dissatisfaction and greater use of the internet for socialising.
  • Heterosexuals exhibited significantly lower online dating behaviour than homosexuals and bisexuals.

Annabel Chan is available for interview.

Media contact: Jim Buckell, A/Senior Media Officer

Marketing and Communications Department, Victoria University

Ph: (03) 9919 4243; mobile: 0400 465 459; email: