| Gamelin et al., 2009 (35) |
To investigate the effects of high intensity intermittent training of short duration on autonomic cardiovascular control. |
52 children. -Training group (n = 26; 15 boys and 11 girls; 9.8 ± 0.7 years). -Control group (n = 26; 14 boys and 12 girls; 9.3 ± 1.2 years). |
Intermittent exercise for 30 minutes, 3 times per week for 7 weeks. The sessions were composed of short and intermittent running with an intensity of between 100 and 190% of maximal aerobic speed (MAS). |
SDNN, rMSSD, LF, HF, SD1 and SD2. |
The high-intensity intermittent training improved aerobic conditioning, but did not affect cardiac autonomic regulation in children. |
| Goulopoulou et al., 2010 (18) |
To analyze the differences in the blood pressure response and cardiovagal autonomic modulation during isometric handgrip exercises between children and adults. |
-23 healthy children aged 7 to 9 years. -23 healthy adults aged 20 to 25 years. |
Participants were seated, positioned with the elbow of the dominant upper limb at 90o. A maximal voluntary strength test (MVS) was performed and the best of three attempts used as the value of MVS. After determining the maximum force, the subjects performed a sustained isometric contraction to 30% of MVS for 3 minutes. |
SDNN*, rMSSDx and HFx. |
The differences in blood pressure responses of children and adults during an isometric contraction cannot be explained by differences in cardiovagal autonomic modulation and appear to be associated with factors that contribute to the force. |
| Iwasa et al., 2005 (36) |
To investigate the relationship between HRV at night and physical activity in children. |
29 children (17 boys and 12 girls; 7.5 ± 1.4 years). |
Using a pedometer and multimemory accelerometer, the authors measured the number of steps and the intensity of the exercise performed during the day. These findings were associated with HRV collected during the night (12 p.m. – 5 a.m.). |
SDNN*, rMSSDx, SDANN, LF, HFx, LF/HF and RR50x. |
Physical activity increases heart rate during sleep, but reduces the activity of the parasympathetic nervous system during the night, characterized by reduction in the HF and RR50 indices. |
| Leicht et al., 2008 (37) |
To examine the moderate term reproducibility of heart rate and frequency domain indices of HRV at rest and during light to moderate exercise in children. |
10 healthy and active children (6 boys and 4 girls, aged 7 to 12 years). |
Training for 8 weeks, continuous walking on a treadmill at 3 workloads: 2 km/h at 0% inclination, 50% and 60% of MHR predicted by age. Each work intensity lasted for 10 minutes. |
FC, LF (ms2/hz), LF* (nu), HFx (ms2/hz), HFx (nu) and LF/HF. |
During eight weeks of training with light and moderate exercise, the reproducibility of HRV was considered low, but there were limitations regarding the sample size, and only measures of HRV in the frequency domain were analyzed. |
| Longin et al., 2009 (33) |
To introduce a battery of autonomic tests, specifically for children and adolescents, to establish normative parameters of HRV and compare the impact of these autonomic tests. |
100 healthy individuals between 6 and 15 years of age (51 girls and 49 boys). -Group of children (5 to 11 years). -Group of adolescents (12 to 15 years). |
Sustained manual isometrics for 2 minutes with 30% of the established maximum power. |
rMSSD (ms), LF (ms2) and HF (ms2). |
The study provides the first normative data for HRV for the battery of autonomic tests specifically for children and adolescents in addition to quantifying autonomic changes induced by the test procedures compared with measurements from the database. |