Walking to school every day may reduce stress levels and lower the risk of suffering from heart problems in adolescents, according to findings published in Medicine and Science in Sports and Exercise.

During a recent study, researchers divided 40 participants aged 10 to 14 into two groups. One group sat in a chair while viewing images of a neighborhood and school grounds, while the others completed a one-mile walk while viewing similar images.

Students were then asked to take a Stroop test, which has participants identify colors in several colored boxes.

While completing this task, the walkers’ heart rate increased by three beats per minute, while the sitting group experienced an increase of 11 beats. Researchers also discovered that the sitters had blood pressure levels that were three times higher than those who did the one-mile walk.

James Roemmich, lead author of the trial, stated that “the cardiovascular disease process begins in childhood, so if we can find some way of stopping or slowing that process, that would provide an important health benefit.” He added that these findings show that “physical activity has a protective effect on the development of cardiovascular disease, and one way it may be doing so is by reducing stress reactivity.”

In 2008, approximately 26.6 million people in the United States were diagnosed with heart disease, the Centers for Disease Control and Prevention (CDC) reports.