Background and purpose: Acceleration of diastolic filling in athletes is higher than healthy people and athletes' morphologic changes and cardiac function is controversial. This study aimed to compare the indices of left ventricular systolic and diastolic function between healthy isometric and isotonic athletes and non-athlete healthy individuals.

Materials and methods: A case-control study was conducted in which healthy isometric athletes (n=25) and healthy isotonic athletes (n=25) as case and non-athlete healthy individuals (n=25) were assessed by transthoracic echocardiography and Tissue Doppler Imaging. Then, the cardiac structural and functional parameters were recorded and analyzed between the groups. Statistical analysis was performed using SPSS V16.

Results: The posterior wall thickness during diastole (PWd), interventricular septal in diastole (IVSd) and LV mass in isometric athletes were significantly higher than those of the control group (P<0.05). The average size of right ventricle was highest (3±0.51 cm) in isotonic and lowest (2.6±0.27 cm) in the control group indicating significant differences between isotonic and control groups (P=0.001) and between isometric and control groups (P=0.02). The difference of mean E wave velocity between isometric and isotonic athletes were significant (0.89±0.13 and 0.81±0.1; P=0.03, respectively).

Conclusion: Isotonic exercises lead to fewer changes on cardiac systolic and diastolic parameters compared with isometric exercises. The only difference between the cardiac effects of isotonic and isometric exercise was observed on E wave velocity. In isometric and isotonic exercises despite ventricular hypertrophy and left ventricular wall thickness, we did not find any disturbances in cardiac systolic and diastolic function.