The study, published in The Lancet Child & Adolescent Health, found that kids aged 11 to 17 years are at the lower levels of insufficient physical activity in Bangladesh and India (where 63 per cent and 72 per cent of boys were insufficiently active in 2016, respectively).
For girls, the lowest levels of insufficient activity were seen in Bangladesh and India, and are potentially explained by societal factors, such as increased domestic chores in the home for girls.
According to the WHO, levels of insufficient physical activity in adolescents continue to be extremely high, compromising 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," said study author Dr Regina Guthold, WHO.
The study also found that more than 80 per cent of adolescents worldwide are not physically active, including 85 per cent girls and 78 per cent boys, putting their health at risk by not doing regular exercise and spending too much time on screen.
For the findings, the researchers estimated how many 11 to 17-year-olds do not meet this recommendation 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.
Based on data reported by 1.6 million 11 to 17-year-old students - the research found that across all 146 countries studied between 2001-2016, girls were less active than boys in all but four (Tonga, Samoa, Afghanistan and Zambia).
According to the study, physical activity trends show slight improvement for boys, none for girls. Most countries in the study (73 per cent, 107 of 146) saw this gender gap widen between 2001-2016.
"The trend of girls being less active than boys is concerning," said study co-author Dr Leanne Riley, WHO.
"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," Riley added.
( With inputs from IANS )