New research shows that school uniform policies can prevent young people from being active, especially primary school-aged girls.

The Cambridge University study used data on physical activity participation from more than a million five- to 17-year-olds internationally. It found that in countries where most schools require students to wear uniforms, fewer young people meet the 60 minutes of physical activity per day recommended by the World Health Organization (WHO).

Regardless of uniform policies, fewer girls than boys reach recommended levels of physical activity in most countries. However, among primary school students, the gap in activity between girls and boys was found to be wider in countries where uniforms are compulsory in most schools. The same result was not found in secondary school age students.

The authors suggest that this may be explained by the fact that younger children engage in more incidental exercise throughout the school day than older students. For example, through running, climbing and various other forms of active play at lunchtime. There is already evidence that girls feel less comfortable participating in active sport if they wear certain types of clothing such as skirts or dresses.

Importantly, the findings do not definitively prove that school uniforms limit children’s physical activity, and the researchers stress that “causation cannot be inferred.” Previous, smaller studies, however, provide support for these findings, indicating that uniform may be a barrier. For the first time, research examines extensive statistical evidence to assess this claim.

The research was led by Dr Mairead Ryan, a researcher at the University of Cambridge’s Faculty of Education and the MRC Epidemiology Unit.

“Schools often prefer to use uniforms for a variety of reasons,” Ryan said. “We’re not trying to suggest a total ban on them, but rather trying to present new evidence to support decision-making. School communities can consider the design, and whether specific features of uniforms should be considered.” Either encourage or restrict any opportunities for physical activity throughout the day.”

The WHO recommends that young people should get at least 60 minutes of moderate physical activity per day during the week. The study confirms previous observations that most children and adolescents are not meeting this recommendation, particularly girls. Across countries, the difference in the percentage of boys and girls meeting physical activity guidelines averaged 7.6 percentage points.

Current evidence suggests that uniform may be a factor. For example, previous concerns were raised about girls’ PE uniforms and school sports kits. A 2021 study in England found that the design of girls’ PE uniforms prevented students from participating in certain activities, while hockey player Tess Howard, after analyzing interview and survey data, proposed redesigning gendered sports uniforms for similar reasons.

However, children often keep their exercise outside of PE and sports lessons. “Activities such as walking or cycling to school, breaktime games, and outdoor play after school can help young people incorporate physical activity into their daily routine,” said Ryan. “That’s why we’re so interested in the extent to which different elements of the youth’s environment, including what they wear, encourage such behaviors.”

The study analyzed existing data on the physical activity levels of nearly 1.1 million young people aged 5 to 17 in 135 countries and combined it with newly collected data on how common school uniform use was in those countries. Is.

In more than 75% of the countries surveyed, most schools required their students to wear uniforms. The study found that participation in physical activity was low in these countries. In countries where uniforms were the norm, the average proportion of all students meeting WHO recommendations was 16%. This rose to 19.5 percent in countries where uniforms were less common.

There was a consistent gender difference between boys’ and girls’ physical activity levels, with boys 1.5 times more likely to meet WHO recommendations at all ages. However, the gap increased from 5.5 percentage points at the primary school level in non-uniform countries to 9.8 percentage points in countries where most schools required uniforms.

This finding matches evidence from other studies showing that girls are more self-conscious about engaging in physical activity when they wear a uniform in which they do not feel comfortable. “Girls may feel less confident about doing things like cartwheels and tumbles on the playground or riding a bike on a windy day if they are wearing a skirt or dress,” said senior author Dr Esther van Sluys, MRC. said the investigator. “Social norms and expectations affect what they can do in these clothes. Unfortunately, that’s a problem when it comes to promoting physical health.”

The study’s authors argue that there is now enough evidence to warrant further investigation into whether or not there is a link between school uniforms and lower activity levels. They also highlight the importance of regular physical activity for all young people, regardless of gender.

“Regular physical activity supports a number of physical, mental and wellness needs, as well as academic outcomes,” Ryan said. “We now need more information to build on these findings, looking at how long students wear their uniforms after school, whether this varies by background, and how How broad gender dress codes can affect their activism.”

are reported in the results Journal of Sport and Health Science.