The first global trends in the lack of physical activity among adolescents have been published and show that urgent action is needed to increase physical activity among girls and boys aged 11 to 17. The study, published in The Lancet Child & Adolescent Health Journal and prepared by researchers from the World Health Organization (WHO), shows that more than 80 percent of adolescents in schools worldwide – 85 percent of girls and 78 percent of boys – do not meet the current recommendation of at least one hour of physical activity per day.
The study – based on data from 1.6 million students aged 11 to 17 years – shows that in all 146 countries surveyed in the period 2001-2016, girls were less active than boys, with four exceptions (Tonga, Samoa, Afghanistan, and Zambia).
In 2016, the difference between the percentage of boys and girls complying with the recommendation was more than 10 percentage points in almost one in three countries (43 in 146 countries, or 29 percent), with the largest differences in the United States and Ireland (more than 15 percentage points). In most of the countries surveyed (107 out of 146, i.e. 73 percent), this gap increased over the period 2001-2016.
The health of young people threatened by lack of physical activity
The authors explain that the lack of physical activity is still a common problem among adolescents and endangers their current and future health. “Urgent policy action to increase physical activity is needed now, particularly to promote and retain girls’ participation in physical activity,” says Dr. Regina Guthold of WHO, one of the authors of the study.
A physically active lifestyle during adolescence is healthy: it improves cardiorespiratory and muscle function, improves bone and cardiometabolic health and has positive effects on weight. There is also increasing evidence that physical activity improves cognitive development and socialization. Evidence shows that many of these effects are still felt in adulthood.
In order to take advantage of these benefits, the WHO recommends that adolescents undertake moderate to vigorous physical activity for at least one hour a day.
In order to estimate how many people aged 11 to 17 do not comply with this recommendation, the authors looked at the data from the school level of physical activity surveys. This assessment covered all types of physical activity, including time spent on active play, recreation, and sport; active household chores; walking, cycling and other forms of active transport; physical education; and planned physical activity.
To improve the level of physical activity among adolescents, the study recommends:
- Urgently expand policies and programs that have proved effective in increasing physical activity among adolescents.
- Undertake multi-sectoral actions in the fields of education, urban planning, and road safety to increase the opportunities for young people to be active.
- The top levels of society, including national and local authorities, should promote the importance of physical activity for the health and well-being of all, in particular, young people.
“The study highlights that young people have the right to play and should be provided with the opportunities to realize their right to physical and mental health and well-being, said Dr. Fiona Bull of WHO, co-author of the report. “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. Policymakers and stakeholders should be encouraged to act now for the health of this and future young generations.”
The development of physical activity has improved slightly for boys but not for girls.
This new study estimated for the first time the trends for the period 2001-2016, extrapolating the trends observed in 73 countries that have carried out several consecutive studies to all 146 countries. Globally, the prevalence of physical inactivity decreased slightly between 2001 and 2016 in boys (from 80 percent to 78 percent), but there was no change in girls (the figure was close to 85 percent).
Countries where the percentage of under-active boys has decreased most are Bangladesh (from 73 to 63 percent), Singapore (from 78 to 70 percent), Thailand (from 78 to 70 percent), Benin (from 79 to 71 percent), Ireland (from 71 to 64 percent) and the United States (from 71 to 64 percent). For girls, however, the changes were not very significant, ranging from a decrease of 2 percentage points in Singapore (from 85 to 83 percent) to an increase of 1 percentage point in Afghanistan (from 87 to 88 percent).
The authors note that if these trends continue, the overall target of a relative reduction of 15 percent in physical inactivity – which would reach a global prevalence of less than 70 percent by 2030 – will not be achieved. This target was agreed by all countries at the World Health Assembly in 2018.
By 2016, the Philippines had the highest prevalence of physical inactivity in boys (93%) and South Korea had the highest prevalence in girls (97%) and both sexes together (94%). Bangladesh was the country with the lowest rates for boys, girls, and both sexes combined (63 percent, 69 percent, and 66 percent respectively).
Countries with the lowest rates of physical inactivity include Bangladesh, India and the United States. The authors note that in Bangladesh and India (where respectively 63% and 72% of boys were insufficiently active in 2016) this can be explained by a focus on national sports such as cricket. The percentage observed in the United States (64%) can be attributed to the good quality of physical education in schools, the high media attention for sport and the accessibility of sporting facilities.
The lack of activity of girls is lower in Bangladesh and India, reportedly due to social factors, including the fact that they take on more domestic tasks.
Lack of activity among adolescents is a major problem
“The trend of girls being less active than boys is concerning, “says Leanne Riley of the WHO. More ways need to be found to meet the needs and interests of girls to encourage them to initiate and continue physical activity as adolescents and adults.
In order to develop physical activity among young people, governments need to identify and address the many causes that identify and address the differences between boys and girls, including social, economic, cultural, technological and environmental inequalities.
According to Dr. Bull countries should develop or update their policies and allocate the resources needed to increase the level of physical activity of all forms, including physical education, active play, and recreation, and provide a safe environment for young people to walk and cycle unattended. Comprehensive action needs to be taken by mobilizing multiple sectors and stakeholders, including schools, families, sports and leisure companies, urban planners and municipal and community leaders.