New research reveals that school uniform requirements may be preventing young people, particularly primary school-aged girls, from participating in physical activity.
The University of Cambridge study analyzed data from over a million five- to seventeen-year-olds around the world. It revealed that in nations where the majority of schools mandate students to wear uniforms, fewer young people fulfill the World Health Organization’s (WHO) recommendation of 60 minutes of physical exercise each day.
Regardless of universal policies, most countries have less girls than boys reaching the required exercise levels. However, in nations where most schools required uniforms, the disparity in activity between boys and girls was shown to be greater. Secondary school kids did not show the same results.
According to the authors, this could be explained by the fact that younger children acquire more incidental exercise throughout the school day than older students, such as running, climbing, and engaging in various forms of physical play during breaks and lunchtimes. There is already evidence indicating girls are less comfortable engaged in energetic play when they are dressed in particular types of apparel, such as skirts or dresses.
Importantly, the results 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 uniforms could pose a barrier. For the first time, the research examines large-scale statistical evidence to assess that claim.
The study was led by Dr Mairead Ryan, a researcher at the Faculty of Education and MRC Epidemiology Unit, University of Cambridge.
Schools often prefer to use uniforms for various reasons. We are not trying to suggest a blanket ban on them, but to present new evidence to support decision-making. School communities could consider design, and whether specific characteristics of a uniform might either encourage or restrict any opportunities for physical activity across the day.
Dr Mairead Ryan
“Schools often prefer to use uniforms for various reasons,” Ryan said. “We are not trying to suggest a blanket ban on them, but to present new evidence to support decision-making. School communities could consider design, and whether specific characteristics of a uniform might either encourage or restrict any opportunities for physical activity across the day.”
The WHO recommends that young people engage in at least 60 minutes of moderate-intensity physical activity each day of the week. The study supports prior findings that most children and adolescents, particularly females, do not fulfill this criterion. Across all countries, the percentage of boys and girls meeting physical activity guidelines varied by 7.6 percentage points on average.
Existing evidence suggests that uniforms may be an issue. Concerns have previously been made about females’ PE outfits and school sports kits. A 2021 research in England discovered that the design of girls’ PE uniforms discouraged kids from participating in specific activities, while hockey player Tess Howard advocated revamping gendered sports uniforms for similar reasons, based on interview and survey data.
Children often get their exercise away from PE and sports lessons, however. “Activities like walking or cycling to school, breaktime games, and after-school outdoor play can all help young people incorporate physical activity into their daily routines,” Ryan said. “That’s why we are interested in the extent to which various elements of young people’s environments, including what they wear, encourage such behaviours.”
The study analyzed existing data on the physical activity levels of approximately 1.1 million young people aged five to 17 in 135 countries, as well as newly obtained data on the prevalence of school uniform use.
In more than 75% of the nations examined, the majority of schools required pupils to wear uniforms. According to the study, physical activity participation in these countries is lower. In countries where uniforms were the norm, the median proportion of all pupils fulfilling the WHO criteria was 16%; in countries where uniforms were less frequent, the figure jumped to 19.5%.
There was a consistent gender gap between boys’ and girls’ physical activity levels, with boys 1.5 times more likely to meet WHO recommendations across all ages. However, the gap widened from 5.5 percentage points at primary school level in non-uniform countries to a 9.8 percentage point difference in countries where uniforms were required in most schools.
The finding appears to match evidence from other studies suggesting that girls are more self-conscious about engaging in physical activity when wearing uniforms in which they do not feel comfortable. “Girls might feel less confident about doing things like cartwheels and tumbles in the playground, or riding a bike on a windy day, if they are wearing a skirt or dress,” said senior author Dr Esther van Sluijs, MRC Investigator. “Social norms and expectations tend to influence what they feel they can do in these clothes. Unfortunately, when it comes to promoting physical health, that’s a problem.”
The study’s authors argue that there is now sufficient evidence to support additional examination into the causal association between school uniforms and lower activity levels. They also emphasize the significance of consistent physical activity for all young people, regardless of gender.
“Regular physical activity helps support multiple physical, mental, and well-being needs, as well as academic outcomes” stated Ryan. “We now need more information to build on these findings, considering factors like how long students wear their uniforms for after school, whether this varies depending on their background, and how broader gendered clothing norms may impact their activity.”
