Abstract
This study analyzed the effects of physical training programs on heart rate
variability, as a measure of sympathovagal balance, in children and adolescents
with chronic diseases. Relevant articles were systematically searched in Pubmed,
Science Direct, Web of Science, Scopus, Google Scholar and Embase scientific
databases. We performed a meta-analysis using an inverse variance heterogeneity
model. Effect size calculation was based on the standardized mean differences
between pre- and post-intervention assessments, assuring at least a single-group
repeated-measures model for each extracted group. Ten studies (252 participants)
were included, seven in obese subjects, two in type-1 diabetes, and one in
cerebral palsy. When time-domain variables were analyzed, exercise was found to
moderately increase RMSSD (SMD=0.478; 95%CI: 0.227 to 0.729;
p <0.001), SDNN (SMD=0.367; 95%CI: 0.139 to
0.595; p =0.002) and pNN50 (SMD=0.817; 95%CI:
0.139 to 0.595; p =0.002). As for frequency-domain variables,
exercise presented a moderate increasing effect on HF (SMD=0.512;
95%CI: 0.240 to 0.783; p <0.001), a negligible effect for
LF (SMD=0.077; 95%CI: –0.259 to 0.412;
p <0.001) and a non-significant reduction for LF/HF
(SMD=–0.519; 95%CI: -1.162 to 0.124;
p =0.114). In conclusion, physical training programs are able to
modulate heart rate variability in children and adolescents with chronic
diseases, affecting mainly the time-domain variables.
Key words autonomic function - exercise - pediatrics - sympathovagal balance - adolescent - heart rate
