Boys and girls as young as 11 struggle to be "just friends" because they are subject to sexual teasing from their classmates, led by a societal pressure to "couple up", according to an in-depth study.

Research by Professor Emma Renold at Cardiff University, in collaboration with the NSPCC, has highlighted the pressure to turn a close boy-girl friendship into a boyfriend-girlfriend relationship from a young age, because of the stigma attached to girls and boys sharing the same interests.

During a qualitative study involving interviews with 125 children aged 10, 11 and 12, one boy admitted that he had to pretend his best friend Alice was a cousin for an entire school year, so that they could hang out free from "heterosexual teasing". One boy talked about how his primary school 'girlfriend' of five years helped him cope with the death of his father.

But, says Prof Renold, the children largely talked about boyfriend-girlfriend cultures as something they had little choice about particpating in.

"Children are actively learning everyday about the contradictory and often confusing ways in which gender and sexuality shape who they are, how they feel in their bodies, what they can do, where they can go, how they relate to others and how others relate to them," she said.

However, the majority of children also spoke of the playground advantages of being in a relationship, such as the enhanced "social status and popularity" being a boyfriend or girlfriend could bring - as well as the social exclusion incurred by not being part of the boyfriend/ girlfriend culture.

One boy admitted it was a "virtual rule" that "if you had a girlfriend you were marked out as cool, if you didn't you were a chav".

Sexual imagery 'bombardment'

The study, carried out to understand how pre-teens feel about growing up in an increasingly sexualised society, also paints an alternative picture for how young boys and girls are responding to the bombardment of sexual imagery on TV and in music videos.

For examples, many girls interviewed for the study said they liked to wear high heels - not to "look sexy" - but to appear older and therefore ward off any bullying or taunts from older girls in their community.

Looking taller, which you can achieve from wearing 5in heels, was not about looks, but about "not being treated like dirt" and being less bullied. One girl said: "Sometimes we do try and look older... when you’re older you have more independence."

Similarly, some boys as young as 11 in the study said they had started weight training to gain a six pack - not to look good - but to protect themselves or their friends from being beaten up.

Prof Renold said: "It wouldn’t make sense just to address this risk by banning magazines advertising high heels for pre-teen girls or tightening up on the age laws of gym membership – it would involve a much broader intervention around physical safety and peer violence, as well as combatting gender and sexual stereotypes."

When it came to the pressure to conform to being in a relationship - even as young as 11 - more girls than boys found it difficult to resist, and it was often talked about as an inevitable part of being a "normal girl" and "something you had to get used to", according to the study.

Boys found it easier to admit they weren't ready to be in a couple, whereas girls were more at risk of harassment, control and coercion from boys, the research said.

Equally, girls were subject to double standards, so they were "frigid" if they didn't want a boyfriend and a "slut" if they talked about it.

Unlike boys, many girls had to negotiate who they were in terms of their relationship status, "We’re either 'single pringles', or 'taken bacon'," one girl said.

Unpicking the findings

Prof Renold said: "When we connect the role of boyfriend to social status, social inclusion and proof of a boys’ masculinity, we can perhaps begin to make some sense of how to intervene in these situations – and again it would involve directly addressing constraining gender norms for boys and girls."

She added that her research was set up to allow children’s own views to take priority - hence personal interviews with children rather than quantitative research - rather than adults assuming they knew the pressures that children were under. "Because when it comes to sexuality, children’s views have either been absent, sidelined, ignored, sensationalised or simplified in popular debate."

Another finding from the study shows girls are having to "put up with living in a sexist society".

"Children also talked at lot about the pressure to conform to gender norms and stereotypes.

"As one girl told me, 'I feel pushed to be a girl'. In contrast to what we hear in the media, many girls preferred comfy clothes, like tracksuit bottoms and hoodies - clothes that concealed rather than revealed the contours of their body. As Steph, age 12, says: 'If I don’t feel good about myself, the last thing I am going to do is draw attention to myself by wearing rude stuff'."

Prof Renold's research comes after a national survey by Girlguiding found three quarters of girls and young women believe sexism affects most areas of their lives, with many subject to sexual taunting or sexist jokes at school.

Nine in 10 of the 1,288 girls and young women interviewed for the Girlguiding study said women are judged for their looks more than their ability, causing one in five girls as young as seven to go on a diet.

Prof Renold said: "Body anxiety was really strong in most girls’ talk about their bodies but was much less present in boys’ talk. Girls spoke a lot about constantly feeling watched and judged."