Children who are more physically active could be less susceptible to respiratory tract infections like the common cold, according to a study published in Pediatric Research Monday, as less than one-quarter of children are estimated to have participated in at least an hour of physical activity each day.
Researchers measured the physical activity levels and symptoms of upper respiratory tract infections—like coughing or sneezing—of 104 children aged 4 to 7 between 2018 and 2019.
As children increased the daily average of steps taken by 1,000, the number of days they experienced symptoms decreased by an average of 4.1 days, while children who participated in three or more hours of physical activity experienced fewer days with symptoms than those who did not.
One group of children whose average daily steps was over 5,600 experienced symptoms more often than another group whose average daily steps was over 9,300.
The study speculates higher physical activity levels result in reduced levels of inflammatory cytokines—proteins associated with chronic inflammation and disease—while improving the immune system’s responses.
The data analyzed by researchers was collected by the childrens’ parents, who reported any illness symptoms as well as whether their child was vaccinated, participated in sports, whether they had siblings and whether they were exposed to second-hand smoke or pet hair.
Despite the reporting of additional data, researchers said they found no association between respiratory tract infection symptoms and sleep patterns, siblings, vaccinations or exposure to pet hair or second-hand smoke.
Only 24% of children aged 6 to 17 participate in at least 60 minutes of daily physical activity, according to the Centers for Disease Control and Prevention. The Office of Disease Prevention and Health Promotion estimates only 25% of adults aged 18 or older participate in enough physical activity.
The amount of physical activity recommended for children depends on their age, according to the CDC, though most health organizations suggest a 60-minute daily average. Regular physical activity in children has already been linked to reduced risk of heart disease, high blood pressure and obesity. Lack of physical activity has been associated with an increased risk of cardiovascular disease, cancer and low bone density, which could lead to osteoporosis. Other studies suggest that increased physical activity could lead to better grades and academic performance in addition to improved cognitive performance.