Modifications Of The Non-Linear Parameters Of The Heart Rate Variability Related To The Systematic Practice Of Physical Exercise

Resumen

Introduction:  In recent  years,  the relationship  between  the systematic  practice  of physical  exercise,  cardiovascular  dynamics  and  the  functioning  of  the  autonomic nervous system has been recognized.

Objective: To determine the modifications that non-linear parameters undergo in the autonomic cardiovascular regulation of the heart rate variability with the systematic practice of physical exercise.

Methods: A retrospective cohort analytical study was conducted from February 2016 to August 2018. Population and sample: 36 individuals (Group 1: 18 high- performance baseball athletes; Group 2:  18 medical students). The  data  were collected  in  the  Biomedical  Basic  Sciences  Laboratory  at  Medical  school  1, University  of Santiago  de Cuba,  through  the 8-channel  PowerLab  polygraph,  and stored using the Kubios Software version 3.0.4 Premium.

Results: Statistically significant differences between means were found in heart rate values (p = 0.000); SD1 (p = 0.025); SD2/SD1 ratio (p = 0.007); sample entropy (p = 0.011); short-term fluctuations α 1 (p = 0.019); mean line length (p = 0.016); max line length (p = 0.001); recurrence rate (p = 0.034); determinism (p = 0.010) and Shannon entropy (p = 0.015). The parameters of SD1 (C = 0.906) and sample entropy (C = 0.712) were significantly associated with a heart rate ≤ 70 beats per minute.

Conclusions: With the systematic practice of physical exercise, the non-linear parameters of the autonomic cardiovascular regulation of the heart rate variability undergoes modifications that respond to a better adaptability of the autonomic nervous system, and to a greater capacity to regulate cardiovascular function.