Effectiveness of Multi-activity, High-intensity Interval Training in School-aged Children.

The present study aimed to evaluate the effectiveness of a school-based multi-activity HIIT on aerobic fitness (AF) and hemodynamic parameters in children. 46 students were randomized into an intervention group (INT) (N=22) and a control group (CON) (N=24). Throughout a 3-month intervention period, both INT and CON participated in the regular physical education classes (PE) twice a week. Only INT received an instructed HIIT during the first 20 min of the PE. In addition to an AF-test, peripheral (pBP) and central (cBP) blood pressure, augmentation pressure (AP), and aortic pulse wave velocity (aPWV) were assessed. Significant differences in intervention effects in favor of INT were detected for AF (7.73, P=0.007), peripheral systolic BP (-6.13 mmHg, P=0.038), central systolic BP (-5.19 mmHg, P = 0.041), AP (-2.02 mmHg, P=0.013), and aPWV (-0.19 m/sec, P=0.031). The regular HITT intervention showed beneficial effects on AF, BP, and parameters of vascular stiffness already in children.