Encourage your children to take long walks, swim, do household chores or cycle daily to fight off the extra kilos of a sedentary lifestyle. — AFP
Moderate-to-vigorous physical activity could be less effective than light physical activity in reducing obesity.
This is the surprising finding of a new international study of over 6,000 children aged 11, followed until the age of 24, which suggested that light but regular physical activity, in the form of long walks, swimming, household chores or cycling, could help prevent obesity linked to a sedentary lifestyle from childhood onwards.
The large-scale study was carried out jointly by the University of Exeter (England), the University of Eastern Finland, the University of Bristol (England), and the University of Colorado (United States), using data from the Avon Longitudinal Study of Parents and Children (ALSPAC).
During the study period when they were aged 11 to 24, the participants wore an accelerometer around their waist to measure their sedentary time, light physical activity and moderate-to-vigorous physical activity at ages 11, 15 and 24.
At the same time, researchers collected data on body fat mass and skeletal muscle mass, as well as fasting blood samples to assess their glucose, insulin and cholesterol levels.
Published in the journal Nature Communications, the results of this work reveal that sedentary time increased over the course of the study, rising from around six hours a day in childhood to nine hours in young adults.
Meanwhile, the time devoted to light physical activity decreased from six to three hours daily.
Only the time spent doing moderate-to-vigorous activity remained stable.
The researchers observed a link between a sedentary lifestyle and an increase in total body fat mass, of the order of 1.3 grammes for every minute of sedentary time.
Of the fat mass acquired during the participants' growth, 7% to 10% could be linked to a sedentary lifestyle.
In contrast, every minute of light exercise was associated with a reduction in total body fat mass of around 3.6g.
Cumulatively, light physical activity could have reduced body fat mass by 950g to 1.5 kilogrammes over the course of the participants' growth.
This result was not observed with moderate-to-vigorous physical activity, even when the famous World Health Organization (WHO) recommendations were met.
Such activity "only" reduced total body fat mass by 70g to 170g over the course of the participants' growth.
"These new findings strongly emphasise that light physical activity may be an unsung hero in preventing fat mass obesity from early life.
"It is about time the world replaced the mantra of ‘an average of 60 minutes a day of moderate-to-vigorous physical activity’ with ‘at least three hours a day of light physical activity’.
"Light physical activity appears to be the antidote to the catastrophic effect of sedentary time in the young population," explained study co-author Dr Andrew Agbaje in a press release.
He concluded: "Our study provides novel information that would be useful in updating future health guidelines and policy statements.
"Public health experts, health policymakers, health journalists and bloggers, paediatricians, and parents should encourage continued and sustained participation in light physical activity to prevent childhood obesity.”
In 2016, nearly two billion adults were overweight, including more than 650 million who were classified as obese, according to data published by the WHO.
At the time, the health authority pointed out that a rise in body mass index (BMI) increases the risk of cardiovascular (heart) disease, musculoskeletal disorders, diabetes and certain cancers. – AFP Relaxnews
