School break times in England have got shorter over the last two decades, with older pupils losing more than an hour a week as lessons increasingly eat into lunch and play time, research has found.

Afternoon break times, once enjoyed by nearly all primary school children, have been “virtually eliminated”, the report found, while a quarter of secondary schools now have lunch breaks of 35 minutes or less.

The UCL Institute of Education study found the youngest primary children, aged five to seven, have 45 minutes less break time per week than children of the same age did in 1995, while secondary pupils aged 11-16 have lost 65 minutes.

Just 15% of children aged seven to 11 and just over half of five to seven-year-olds now have an afternoon break. Back in 1995, 13% of secondary school pupils were still enjoying an afternoon break period but by 2017 that figure had shrunk to 1%.

Lunch breaks have been similarly trimmed. In 1995 just under a third of secondary schools (30%) had a lunch break of less than 55 minutes, but by 2017 that had gone up to 82%. The main reason given by schools is to allow more time for teaching and learning in order to cover the curriculum. Another reason, the report suggests, is to limit poor behaviour at lunch time.

Academics who conducted the research are concerned about the impact of reduced break times on children and young people’s development, and warn they are losing valuable opportunities to make friends, develop social skills and exercise.

They are also worried too many children are losing their lunch and break times as a punishment. According to the study, 60% of schools withhold breaks from children, often because of poor behaviour or the need to complete work.

“At a time of growing concern about children’s mental health and personal and social development,” the report said, “every school pupil should have the opportunity for break times in the school day.”

The report’s lead author, Ed Baines, said: “Despite the length of the school day remaining much the same, break times are being squeezed even further with potential serious implications for children’s wellbeing and development.

“Not only are break times an opportunity for children to get physical exercise – an issue of particular concern given the rise in obesity, but they provide valuable time to make friends and to develop important social skills – experiences that are not necessarily learned or taught in formal lessons.”

The study, funded by the Nuffield Foundation and based on data from more than 1,000 primary and secondary schools collected in 1995, 2006 and again in 2017, also looks at how young people’s social lives have changed over two decades.

It found fewer pupils were meeting up with friends in person after school. In 2017 31% of children reported they seldom got to meet peers and friends, compared to 15% in 2006. Against that backdrop, researchers say break times in school are even more important to young people’s development.

“Whereas at one time afternoon breaks were a daily experience for nearly all primary school children, now they are increasingly a thing of the past. And there has also been a decline in lunch breaks, which is of particular concern,” said Baines.

“Children barely have enough time to queue up and to eat their lunch, let alone have time for other things like socialising, physical exercise, or exploring self-chosen activities.”

The report calls on schools to stop shortening break times and to scrap the practice of withholding breaks. It also asks policymakers to consider legislating on the issue. “Working adults, including teachers, have a right to breaks but there is no equivalent policy for pupils,” it states.

A Department for Education spokesperson said it was up to schools to decide on the structure and duration of the school day. “However, we are clear that pupils should be given an appropriate break and we expect school leaders to make sure this happens.”