Abstract

Background: Regular physical training in young athletes leads to physiological cardiovascular adaptations, often manifested as electrocardiographic (ECG) changes. Identifying predictors of such changes is essential for distinguishing normal adaptations from potential pathological findings. Objective: The aim of this study was to investigate body mass index (BMI), systolic and diastolic blood pressure (SBP/DBP), and heart rate (HR) as potential predictive factors for sinus arrhythmia, incomplete right bundle branch block (IRBBB), and ST-segment elevation in young endurance and strength athletes. Methods: This retrospective-prospective study included 60 male athletes aged 12–17 years (30 endurance, 30 strength athletes) who underwent a five-year follow-up with regular ECG monitoring. Anthropometric and cardiovascular parameters (BMI, SBP, DBP, HR) were recorded, and associations with ECG findings were analyzed using descriptive statistics, Student’s t-test, Mann-Whitney U test, Chi-square test, and logistic regression. Results: Endurance athletes showed a significant increase in BMI during follow-up (p = 0.035), while in strength athletes BMI was significantly associated with sinus arrhythmia (p = 0.045). Systolic blood pressure at the end of the study significantly differed in endurance athletes with and without ST-segment elevation (p = 0.029). However, logistic regression analysis demonstrated that BMI, SBP, DBP, and HR were not independent predictors of ECG abnormalities in either group. Conclusion: Basic cardiovascular parameters such as BMI, blood pressure, and heart rate do not appear to independently predict ECG changes in young athletes. Other factors, including training intensity and genetic predisposition, likely play a greater role. Preventive cardiovascular screening remains crucial for the early detection of clinically relevant abnormalities in this population.

Key words: Electrocardiography, Athletes, Body Mass Index, Blood Pressure, Heart Rate, Sports Medicine.