SINGAPORE - Children in Singapore gained weight after the two-month long circuit breaker, which saw residents adhering to a strict stay-at-home order from April 2020, a local study has found.
Researchers noted that even after measures were relaxed from June 2 that year, a "substantial proportion" of children stopped outdoor play for a further one to three months.
The weight gained was not insignificant.
For example, the median weight for school-aged boys, nine to 11 years old, had increased from 28.8kg before February 2020, to 38.3kg after August 2020.
This meant their median body mass index (BMI) had increased from 16.3 to 19.1 units.
The research team said the study is unique as it is the first to establish a link between specific changes in behaviour during the pandemic and longer-term changes resulting in increased body mass in children.
The study was helmed by Dr Jonathan Huang, a principal investigator at the Agency for Science, Technology and Research (A*Star).
The research was conducted in collaboration with clinician-scientists from KK Women's and Children's Hospital (KKH), National University Hospital and the National University of Singapore's Yong Loo Lin School of Medicine.
The team found that of the 585 children they monitored, more than a third of school-goers and a quarter of pre-school-aged kids did not have any outdoor play two months after the circuit breaker period.
When their body mass index (BMI) was checked about a year post-circuit breaker, the school-aged children who ceased outdoor activity had a higher BMI reading, by at least half a unit, with boys on average putting on more weight than girls.
"Many pandemic studies in other countries have looked at changes during and after their lockdown periods.
"What's unique about Singapore and our study is that we had a short circuit breaker and a lot of activities resumed soon after, yet a substantial number of children had reported elimination of all outdoor activities, which could have led to an increase in body mass among this group," said Dr Huang, who was the lead author of the study.
In a joint statement on Thursday (March 10), the researchers said previous studies have established strong links between obesity in children and adults.
For example, a Health Promotion Board study in 2017 showed that 70 per cent of overweight children later became obese adults.
Obesity has a correlation with chronic diseases such as diabetes, high blood pressure and heart disease later in life if left unattended.
The researchers also noted that school-aged obesity has been climbing in recent years, a trend confirmed in the National Population Health Survey conducted from July 2019 to March 2020.
Ms Sum Ka Kei, an epidemiologist at A*Star's Singapore Institute for Clinical Sciences, said active play indoors may not be sufficient to replace outdoor activity, particularly in children who are older.
"It is important to understand how to address this effectively, as outdoor time is associated with numerous other benefits to children, including better sleep, learning and socio-emotional development," said Ms Sum, who is the first author of the study.
Professor Fabian Yap, the head and senior consultant at the endocrinology service of the department of paediatrics at KKH, said that the hospital's guidelines offer suggestions for activities across four areas - physical activity, sedentary behaviour, sleep and diet - within a 24-hour period.
These lay the foundation for good health and help prevent the development of chronic diseases, he added.
Moving forward, the researchers will also look at the long-term consequences of changes in children's sleep, family income and other factors that have disrupted lives over the past two years.
The aim is to use the data to understand different family and social dynamics, as well as the motivations underlying such behavioural changes, and design potential interventions that could be applied beyond the pandemic.