Assessment of heart rate variability (HRV) is increasingly used to evaluate dynamic features of cardiovascular (cv) control mechanisms and offers unique insight into autonomic cv modulation in health and disease outcomes. Regular exercise is known to positively influence hemodynamics and various cv risk factors. The present study aimed to evaluate the efficacy of a nine-month moderate interval-training program on HRV, pulse wave velocity (PWV) and systolic blood pressure in elementary school children.
68 students (8.6 ± 0.5 years, 49% girls, BMI 17.9 ± 2.5 kg/m2), were randomized into intervention (IG) (n = 34) and control (CG) (n = 34) group. Both IG and CG had regular physical education classes (PE) (3x45 min/week). During a nine-month intervention period, the IG received an additional exercise intervention program (2x45 min/week). This evaluated exercise program was carried out by trained instructors and comprised an “intense joyful-movement” program equivalent to a moderate interval training.Measures of HRV, PWV, and systolic blood pressure were obtained before and after the intervention program.
IG showed positive modifications of HRV,PWV and systolic blood pressure. After the intervention, HF-Power increased from 35.0 ± 2.1% to 42.6 ± 2.37% (p < 0.001), and the Low-Power decreased from 48.4 ± 1.6% to 44.7 ± 1.8 % (p = 0.025) in the IG. In the IG and CG the HF-Power (p < 0.001) and LF-Power (p = 0.003) evolved differently during the intervention period. The LF/HF ratio change was different in both groups (p < 0.020). The IG showed a reduction of the mean value from 1.6 ± 0.2 % to 1.3 ± 0.1%, while the LF/HF-ratio of the CG increased from 1.2 ± 0.1% to 1.5 ± 0.2 %. The PWV decreased from 4.,80 m/s to 4.56 m/s in the IG, while the PWV in the CG increased from 4.56 m/s to 4.66 m/s (p < 0.001). The peripheral (p < 0.001) and central (p = 0.052) systolic blood pressure also evolved in favor of the IG.
Among elementary school children additional moderate intensity interval-training program had favorable effects on hemodynamic parameters and on measures of cardiac autonomic control due to increasing cardiac vagal activity. Exercise time should be increased as early as possible to positively influence cardiac autonomic function and potentially reduce cardiovascular morbidity in later life.
1Charité- Universitätsmedizin Berlin Institut für Sozialmedizin, Epidemiologie und Gesundheitsökonomie, Berlin, GERMANY
2Martin-Luther-Universität Halle Institut für Sportwissenschaften, Berlin, GERMANY
3Charité- Universitätsmedizin Berlin Institut für Sozialmedizin, Epidemiologie und Gesundheitsökonomie, Berlin, GERMANY
4Medical School Berlin, Berlin, GERMANY
5Charité- Universitätsmedizin Berlin Institut für Sozialmedizin, Epidemiologie und Gesundheitsökonomie, Berlin, GERMANY
6Medical School Berlin, Berlin, GERMANY