Effect of a simulated active commute to school on cardiovascular stress reactivity.

Abstract

Stress-induced cardiovascular reactivity is associated with the pathogenesis of cardiovascular disease. This study tested whether a simulated active commute to school dampened cardiovascular reactivity to a cognitive stressor typical to what children might experience during school. Forty children (20 girls and 20 boys) aged 10-14 yr were randomly assigned to simulated sedentary drive-to-school or active-commute (walking) groups. The walking group completed a self-paced 1.6-km walk on a treadmill while images from a real 1.6-km walk through a pleasant neighborhood that finished at a school were projected in front of them. The drive-to-school group sat in a chair and watched the same slideshow of images of the neighborhood environment. Standardized residualized gain scores of cardiovascular reactivity during a cognitive stressor, the Stroop task, were calculated and used as dependent variables. Children in the walking group self-selected a walking intensity of 60.6% +/- 1.6% HRmax and covered the 1.6-km distance in 21.5 +/- 0.5 min. Children in the walking group had lower HR (2 +/- 1 vs 11 +/- 1 bpm, P < 0.001), systolic blood pressure (4 +/- 1 vs 12 +/- 1 mm Hg, P < 0.001), pulse pressure (-4 +/- 1 vs 6 +/- 1 mm Hg, P < 0.001), and perceived stress (1.4 +/- 0.1 vs 3.0 +/- 0.1 cm, P < 0.001) reactivities to cognitive stress than the control group. Active commuting to school may dampen cardiovascular reactivity and perceived stress when confronted with stressful cognitive challenges during the school day. This may help reduce the risk for cardiovascular disease later in life.