March 8, 2013, The New York Times
By Jan Hoffman
Physically active children generally report happier moods and fewer symptoms of depression than children who are less active. Now researchers may have found a reason: By one measure, exercise seems to help children cope with stress.
Finnish researchers had 258 8-year-old boys and girls wear accelerometers on their wrists for at least four days that registered the quality and quantity of their physical activity. Their parents used cotton swabs to take saliva samples at various times throughout a single day, which the researchers used to assess levels of cortisol, a hormone typically induced by physical or mental stress. Continue reading