Effects of athletic training on heart rate variability triangular index

Area of Science:

• Sports Science
• Cardiology
• Physiology

Background:

• Heart rate variability (HRV) is a key indicator of autonomic nervous system function.
• The heart rate variability triangular index (HRVI) is a measure derived from HRV analysis.
• Understanding HRV in elite athletes can provide insights into physiological adaptations to training.

Purpose of the Study:

• To assess the heart rate variability triangular index (HRVI) in elite track and field athletes.
• To compare HRVI across different athletic disciplines (long-distance runners, speed runners, throwers) and non-trained individuals.
• To investigate the relationship between HRVI, maximal oxygen consumption (VO2max), and cardiac structure.

Main Methods:

• Spirometric testing, m-mode echocardiography, and 24-hour ambulatory ECG monitoring were performed.
• Participants included 60 healthy males: 15 long-distance runners, 15 speed runners, 15 throwers, and 15 non-trained controls.
• Time-domain HRV analysis was used to calculate HRVI, mean heart rate, R-R interval, and SDRR.

Main Results:

• Elite athletes, particularly long-distance runners, exhibited significantly higher HRVI and SDRR compared to non-trained subjects.
• Long-distance runners showed the highest HRVI and VO2max values.
• HRVI demonstrated a significant positive correlation with VO2max and end-diastolic volume index (EDVI) in endurance-trained athletes.

Conclusions:

• Exercise training patterns significantly influence heart rate variability triangular index (HRVI) in athletes.
• HRVI is dependent on VO2max levels in endurance-trained athletes.
• HRVI is not significantly related to myocardial hypertrophy (LVMI) across all training types.