Four in five 11- to 17-year-olds around the world are not taking enough physical exercise, according to the first such analysis.
The World Health Organization says children’s health is being damaged as well as their brain development and social skills.
It says failing to take the recommended hour a day of exercise is a universal problem in rich and poor countries.
Boys were more active than girls in all but four of the 146 countries studied.
Pretty much anything that makes the heart beat more quickly and the lungs breathe harder.
It could include:
- running
- cycling
- swimming
- football
- hopping
- skipping
- gymnastics
The target is 60 minutes of moderate-to-vigorous exercise a day.
“I don’t regard it as a ridiculous target,” the WHO’s Dr Fiona Bull says.
“It is evidence-based to establish good health and development.”
The difference between moderate and vigorous is you can still have a natter while doing moderate exercise but vigorous exercise would leave you too breathless to chat.
The main reason is health, both now and in the future.
In the short term, being active means:
- fitter heart and lungs
- stronger bones and muscles
- better mental health and wellbeing
- lower weight
“Active adolescents are likely to be active adults,” the WHO’s Dr Regina Guthold says.
And over a lifetime being active can decrease the risk of many diseases, from heart attacks and stroke to type-2 diabetes.
But the researchers say there is also growing evidence being active is good for the developing brain.
“They have better cognitive function, easier learning, they have better pro-social behaviour,” Dr Guthold says.
Do these findings just tell us something fundamental about children, and indeed all of us, that we’ll just crash on the sofa given half a chance?
“Children are not lazy,” Dr Bull says.
“This tells us something universal but it’s not about children. It’s the neglect and failure of us to prioritise physical activity – and that seems to be worldwide.”
There is no single answer that explains why activity levels are so low but there are some common themes.
One is the focus on academic performance over physical fitness.
“Young people in this age group are very encouraged to work hard, to study for exams,” says Leanne Riley, one of the report’s authors.
“Often for very long periods of the day, they’re sitting in school doing homework and then they’re not getting these opportunities to be more active.”
The researchers also say there are issues around ensuring sport and leisure facilities are safe, accessible and affordable.
