Almost a quarter of adolescents aged 11 to 17 report not a single day in the previous week with 60 minutes of moderate to vigorous physical activity, according to estimates published by the World Health Organisation.
The study, published in The Lancet Global Health on 4 November, draws on 389 surveys covering more than 3.2 million adolescents in 140 countries and finds that global progress on adolescent activity has stalled for 15 years.
What the data shows
Some 240 million of the world’s 950 million adolescents reported no active day in the previous week, a prevalence of 24.9 per cent. The average was 2.7 active days a week, and only 14 per cent were active on all seven days.
Girls were less active than boys on both measures. Twenty-eight per cent of girls reported no active days, compared with 22 per cent of boys, and only 11 per cent of girls were active every day against 17 per cent of boys. The pattern held in almost every country and region.
Country results ranged from about 4 per cent to more than 40 per cent of adolescents reporting no active days, a spread that suggests the problem is shaped by environment rather than by individual motivation.
Why the numbers matter
Physical inactivity in adolescence predicts inactivity in adulthood, and inactive adults carry higher risks of cardiovascular disease, type 2 diabetes, some cancers and poor mental health. The habits formed between 11 and 17 are difficult to change later.
The WHO recommends that adolescents do at least 60 minutes of moderate to vigorous activity a day. That target is met by a minority in every country surveyed, and the shortfall is largest among girls, poorer households and children in cities where safe space is scarce.
The organisation’s director-general, Tedros Adhanom Ghebreyesus, said the answer is not to tell adolescents to try harder but to build schools, streets and communities where activity is safe and normal. That framing shifts responsibility from individuals to the design of everyday environments.
What drives inactivity
The study points to a set of connected causes: transport patterns that make walking and cycling unsafe or impractical, the loss of safe public space, school environments that devote less time to physical education, the cost of organised sport, and screens that occupy the hours when children used to play outside.
These are policy questions rather than medical ones. A city that builds protected cycle lanes, keeps parks open and funds school sport will produce more active children than one that runs advertising campaigns telling them to move more.
The gender gap is the most stubborn finding. In many countries girls report less freedom to travel independently, fewer facilities that feel safe and less encouragement to take part in sport. Programmes that have narrowed the gap have typically changed the offer rather than the message, providing activities that girls want to do, at times and places they can reach.
What happens next
The estimates will feed into national reporting on the sustainable development goals, where adolescent activity is one of the indicators that most countries are off track on. They also arrive ahead of a WHO push to tie physical activity into planning, transport and education policy rather than treating it as a health responsibility alone.
The study’s authors note that the data predates the most recent changes in adolescent screen use and that the picture may be worse now than the survey period suggests. The next round of global estimates is not due for several years, by which time a further cohort will have passed through adolescence without establishing the habit.
