The World Health Organisation (WHO) has warned that the majority of adolescents worldwide are not sufficiently physically active, putting their current and future health at risk.

A WHO-led study, published in The Lancet Child & Adolescent Health journal, shows that "urgent action" is needed to increase physical activity levels in girls and boys aged 11 to 17 years.

The study reveals that more than 80 per cent of school-going adolescents globally do not meet current recommendations of at least one hour of physical activity per day – including 85 per cent of girls and 78 per cent of boys.

Of the 146 countries studied for the report, girls were less active than boys in all but four (Tonga, Samoa, Afghanistan and Zambia).

“Urgent policy action to increase physical activity is needed now, particularly to promote and retain girls’ participation in physical activity,” said study author Dr Regina Guthold.

To improve levels of physical activity among adolescents, WHO says that "urgent scaling up" is needed of known effective policies and programmes to increase physical activity in adolescents.

It also calls for multisectoral action in order to offer opportunities for young people to be active, involving education, urban planning, road safety and others.

"The highest levels of society, including national, city and local leaders, should promote the importance of physical activity for the health and well-being of all people, including adolescents," the WHO said in a statement.

Dr Fiona Bull, co-author of the study, added: "Strong political will and action can address the fact that four in every five adolescents do not experience the enjoyment and social, physical, and mental health benefits of regular physical activity.

"Policy makers and stakeholders should be encouraged to act now for the health of this and future young generations."

The WHO report is based on data reported by 1.6 million 11 to 17-year-old students across 146 countries.

The authors estimated how many of the participants did not meet the current WHO recommendation – of an hour of moderate or vigorous physical activity each day – by analysing data collected through school-based surveys on physical activity levels.

The assessment included all types of physical activity, such as time spent in active play, recreation and sports, active domestic chores, walking and cycling or other types of active transportation, physical education and planned exercise.

To read the full report, click here for The Lancet Child & Adolescent Health