Are today's children least fit? Majority of 11- to 17-year-old students globally are not physically active enough, placing their health at risk
Girls are less active than boys, and this gap has grown between 2001-2016, with the biggest differences seen in the US and Ireland; There have been small reductions in insufficient activity among boys, shows analysis based on data from 146 countries.
More than four in five school-going students in the 11–17 age group are not sufficiently physically active, putting their health at risk. Girls are less active than boys, and this gap has grown significantly between 2001-2016, according to a study representing 1.6 million students.
According to the findings -- based on data from 298 school-based surveys from 146 countries -- an estimated 81% of school-going adolescents globally did not meet current recommendations of at least one hour of physical activity per day, which includes 84.7% of girls and 77.6% of boys. The researchers from the World Health Organization (WHO), who conducted the study, say that levels of insufficient physical activity in adolescents continue to be extremely high, compromising their current and future health.
Across all 146 countries, girls were less active than boys in all but four (3%) countries - Tonga, Samoa, Afghanistan, and Zambia. In 2016, in 27 countries, 90% or more of girls did not reach sufficient levels of activity, whereas this was the case for only two countries for boys.
Dr. Regina Guthold, study author from WHO, says: "Urgent policy action to increase physical activity is needed now, particularly to promote and retain girls' participation in physical activity."
"The trend of girls being less active than boys is concerning. More opportunities to meet the needs and interests of girls are needed to attract and sustain their participation in physical activity through adolescence and into adulthood," says study co-author Dr. Leanne Riley from WHO.
The difference in the proportion of boys and girls meeting the recommendations was greater than 10 percentage points in almost one in three countries in 2016 - that is, 29% or 43 countries - with the biggest gaps seen in the US and Ireland. In these two countries, the difference was more than 15 percentage points. Most countries -- that is 73% or 107 of 146 -- saw this gender gap widen between 2001-2016.
"Differences in prevalence of insufficient physical activity between boys and girls and widening gaps over time were particularly apparent in some high-income countries, such as Singapore, the US, and Ireland, all showing an absolute difference in prevalence between boys and girls of more than 13 percentage points in 2016 - an increase in sex difference of more than 5 percentage points relative to 2001," says the report on global trends for adolescent insufficient physical activity, published in The Lancet Child & Adolescent Health journal.
In 2018, WHO launched More Active People for a Healthier World, a global action on physical activity, including new targets of a 15% relative reduction of the worldwide prevalence of insufficient physical activity by 2030 among adolescents and adults.
"The health benefits of a physically active lifestyle during adolescence are well documented. They include improved cardiorespiratory and muscular fitness, bone and cardiometabolic health, and positive effects on weight status. Current evidence suggests that many of those health benefits carry forward into adulthood. Further, there is a growing body of evidence suggesting a positive impact of physical activity on cognitive development and prosocial behavior," says the study.
To achieve these benefits, the international recommendations from WHO and 2018 US guidelines call for adolescents to do 60 minutes or more of daily physical activity of moderate-to-vigorous intensity.
In their study, the researchers estimated how many 11- to 17-year-olds do not meet this recommendation by analyzing 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.
Trends show slight improvement for boys, none for girls
Globally, the prevalence of insufficient physical activity slightly decreased in boys between 2001 and 2016, but there was no change over time in girls.
"Between 2001 and 2016, prevalence decreased by 2.5 percentage points for boys (from 80.1% to 77.6%), whereas there was no significant change for girls (from 85.1% to 84.7%), leading to a significant global difference of 7.1 percentage points in insufficient activity between sexes in 2016. If these trends continue, the global target of a 15% relative reduction in insufficient physical activity -- which would lead to a global prevalence of less than 70% by 2030 -- will not be met by 2030," says the study.
The analysis shows in 2016, prevalence of insufficient physical activity was more than 80% in 71 countries analysed for boys versus 141 (97%) for girls. "It was more than 85% in 20 (14%) countries for boys versus 112 (77%) countries for girls, and more than 90% in two (1%) countries for boys versus 27 (18%) countries for girls," says the study.
The countries that had the greatest decreases in boys being insufficiently active were Bangladesh (from 73% to 63%), Singapore (78% to 70%), Thailand (78% to 70%), Benin (79% to 71%), Ireland (71% to 64%), and the USA (71% to 64%). However, among girls, changes were small, ranging from a two-percentage-point decrease in Singapore (85% to 83%) to a one-percentage-point increase in Afghanistan (87% to 88%).
According to the analysis, in 2016, the Philippines had the highest prevalence of insufficient activity among boys (93%), while South Korea had the highest levels among girls (97%), and both genders combined (94%). Bangladesh had the lowest prevalence of insufficient physical activity among boys, girls, and both sexes combined - 63%, 69%, and 66%, respectively.
Three countries -- US, Bangladesh, and India -- had some of the lowest levels of insufficient activity in boys. The researchers say that the lower levels of insufficient physical activity in Bangladesh and India (where 63% and 72% of boys were insufficiently active in 2016, respectively) may be explained by the strong focus on national sports like cricket.
Some of the lowest levels of insufficient activity in boys were found in high-income western countries and South Asia, driven by countries with large populations like the US, Bangladesh, and India. The quite low prevalence of insufficient activity in boys in Bangladesh and India (where 63% and 72% of boys were insufficiently active in 2016, respectively) might be explained by the strong focus on national sports, such as cricket, which is frequently played unstructured in local communities, says the team.
According to the researchers, in the US, these rates (64%) may be driven by better physical education in schools, the pervasive media coverage of sports, and a strong presence of sports clubs providing opportunities to play in structured, organised sport - such as ice hockey, American football, basketball, or baseball.
There was no clear pattern in prevalence according to country income group: insufficient physical activity was 84·9% in low-income countries, 79.3% in lower–middle-income countries, 83.9% in upper–middle-income countries, and 79.4% in high-income countries in 2016.
The researchers recommend that policy action - aimed at increasing physical activity - should be prioritized, adding that stronger government and stakeholder leadership is needed to support the scaling of responses across multiple sectors.
"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 wellbeing," says co-author Dr. Fiona Bull, WHO.
"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," says Dr. Bull.