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Updated: Apr 26, 2026
Autonomic Function Following Concussion in Youth Athletes: An Exploration of Heart Rate Variability Using 24-hour Recording Methodology
Published on: September 21, 2018
Heart rate variability and cardiovascular risk factors in adolescent boys
Breno Q Farah1, Mauro V G Barros1, Babu Balagopal2
1Associate Graduate Program in Physical Education, University of Pernambuco, Recife, PE, Brazil.
Objective:
To establish reference values of heart rate variability (HRV) measures in a cohort of adolescent boys and to determine the relationship between HRV and the clustering of risk factors (RFs) for cardiovascular disease.
Study Design:
This cross-sectional study included 1152 adolescent boys (age: 16.6 ± 1.2 years old). Demographic data, health-related habits, obesity indicators, and blood pressure were evaluated. HRV measures of time (SD of all RR intervals, root mean square of the squared differences between adjacent normal RR intervals, and the percentage of adjacent intervals over 50 ms) and frequency domains were assessed (low [LF] and high [HF] frequency).
Results:
The components of HRV were RR interval (827 ± 128 ms), SD of all RR intervals (61.9 ± 23.5 ms), root mean square of the squared differences between adjacent normal RR intervals (54.5 ± 29.4 ms), percentage of adjacent intervals over 50 ms (29.4 ± 20.4%), LF (53 ± 16 nu), HF (47 ± 16), and LF/HF (1.44 ± 1.08). Greater sympathetic and lower parasympathetic modulation at rest were associated with higher adiposity, higher blood pressure and physical inactivity. Adolescents with 2 or more RFs also presented lower HRV than subjects with no RFs (P < .001).
Conclusions:
The study has provided descriptive indicators that help the interpretation of HRV results in adolescents. Lower HRV measures are associated with the clustering of cardiovascular RFs.
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