Athletes’ heart structural and functional characteristics

Abstract

Cardiac adaptation to sport training depends on a sport specialization. Training in endurance sports causes the left ventricular cavity dilatation and minor increase of the wall thickness. The athletes trained in the endurance sports have high stroke volumes and low heart rate values in the rest and during the physical load. Resistance training leads to increase of the left ventricular wall thickness. The aim of investigation was to estimate the heart structural and functional characteristics of winter biathlon skiers, road cyclists and basketball players of the Latvian Olympic Team. Latvian elite male athletes voluntarily participated in this investigation performed in the Laboratory of the Latvian Olympic Team and Latvian Academy of Sports Education. 20 winter biathlon skiers, 14 cyclists and 15 male basketball players participated in the investigation. The structural cardiac adaptation (a left ventricular posterior wall thickness, a left ventricular end diastolic cavity size, a left ventricular end diastolic volume and a heart stroke volume) is estimated by echocardiography (the equipment Vivid 4, General Electric, Israel). The heart functional adaptation to the endurance training is determined on a mechanical bicycle ergometer (Monark, Sweden). The intensity of exercises increased step by step from 0,5 to 2 W/kg, the exercises intensity - heart rate relationship is determined. An electrocardiogram was registered during the test to determine the heart rate. Echocardiography characteristics in the athletes do not exceed the upper limits for male athletes. The left ventricular posterior wall thickness is < 14 mm and the left ventricular end diastolic cavity size is < 66 mm. The mean left ventricular end diastolic cavity size and volume are greatest in the basketball players due to greatest height and weight of these athletes. The heart stroke volume is significantly larger (p < 0.05) in the winter biathlon skiers (91.3 ± 13.5 cm3) and cyclists (96.2 ± 16.2 cm3) in comparison to the basketball players (76.7 ± 15.7 cm3). It confirms better heart structural and functional adaptation of the athletes trained in winter biathlon and cycling to endurance exercises than in the basketball players. The basketball players has higher average heart rate values than the athletes trained in biathlon and cycling during the same mild and moderate intensity exercises performed on the ergometer. It means that the endurance of the basketball players is lower in comparison with the biathlon skiers and cyclists.