PERSONALIZED ANALYSIS OF CARDIAC REMODELING AT THE END OF THE PREPARATORY PERIOD IN CROSS-COUNTRY SKIERS STRATIFIED BY MOVEMENT SPEED

Abstract

Aim. This study provides an individualized analysis of cardiac remodeling in qualified cross-country skiers stratified by movement speed and identifies characteristics reflecting individual mechanisms of adaptive structural and functional changes in the cardiac hemodynamic system at the end of the preparatory period. Materials and methods. The study involved male athletes who provided written informed consent, underwent a medical examination, and were approved for training and competitive loads. Based on physical performance testing during double poling on a Concept 2 SkiErg (USA), cross-country skiers (n = 20) were divided into leader (n = 10) and reserve groups (n = 10) according to movement speed (km/h). From each group, athletes with the highest and lowest physical performance values relative to the group mean were selected: Leader 1 and Leader 10, Reserve 1 and Reserve 10, respectively. Cardiac morphometric measurements were obtained via transthoracic echocardiography (ECG) using a Mindray DC-70 (China) system in compliance with international ECG protocols. Results. Cross-country skiers demonstrated adaptive cardiac changes characteristic of high-intensity exercise. The leader group mainly showed changes associated with increased diastolic function and cardiac volumes. In the reserve group, adaptation manifested as myocardial hypertrophy and contractile changes, which may be less efficient. Conclusion. The results obtained contribute to a deeper understanding of individual adaptive changes in athletes and help opti­mize the training process.