LEFT-VENTRICULAR FUNCTION DURING EXERCISE IN ATHLETES AND IN SEDENTARY MEN

Aim of this study was to evaluate left ventricular function during exe rcise, in 10 male elite runners and in 10 sedentary males. End-diastol ic (EDV) and end-systolic volume (ESV), left ventricular ejection frac tion (EF), early peak transmitral flow velocity (peak E), time-velocit y integral of mitral inflow (m-TVI); mitral cross sectional area (m-CS A); mitral stroke volume (SV), and cardiac output (CO) were measured b y echo-Doppler. We simultaneously analyzed: VO2max by spirometric meth od, mean arterial blood pressure (MAP) by sphygmomanometer, and heart rate (HR) by ECG. The parameters were measured under basal conditions (level 1), at 50% of maximal aerobic capacity (level 2), at peak of ex ercise (level 3) and during recovery. Ejection fraction in athletes in creased significantly at peak of exercise through Frank-Starling mecha nism. Stroke volume and cardiac output increased significantly in athl etes at peak of exercise. Left ventricular diastolic function was supe rior in athletes versus controls: in fact, higher peak E in athletes e nhanced early diastolic ventricular filling. Therefore, the athletes s howed complex cardiovascular adjustments induced by training, which al lowed an higher peak working power, a greater cardiac output, and VO2m ax when compared with an untrained control population.