Active Kids Have Fewer Sick Days
Children's Health Needs Boost From Physical Activity
Dec. 23, 2003 -- Time spent in sports keeps kids from getting sick -- and it melts body fat, all of which improves children's health, a new study shows.
It's another reason to get children away from computers and TV, and send them outside for exercise.
Habitual physical activity of more than three hours a day gives children the best defense against infections such as colds and flu, writes researcher Thomas J. Cieslak, with Brock University in Ontario, Canada. His study appears in the current Journal of Applied Physiology.
Exercise has positive impact on the immune system, the body's defense against infection, writes Cieslak. Studies show that moderate exercise and physical activity enhance immunity and reduce the rates of upper respiratory infections such as colds. . Moreover, stress and obesity suppress the immune system -- although studies have mostly looked at this in adults, he explains.
"It has long been suspected that the younger the individual, the less effective the immune defense," writes Cieslak. However, a child's immunity is still developing until the ages of 9 to 11, he says. Also, studies of children's health and immunity haven't taken into account diet, climate, and living in densely populated areas.
Effects of the child's physical activity level have also not been studied. However, one recent study found that teens that spend less time in sports activities have more colds and flu, writes Cieslak.