Abstract
Background: Top-level physical training is often associated with morphological changes in heart including increased left ventricular cavity dimension, wall thickness and mass. The objective of this study was to find out the differences in ventricular chamber size and wall thickness in Pakistani elite endurance athletes as compared to age and Body Mass Index matched controls. Material & Methods: This comparative cross-sectional study was conducted in Department of Physiology, Army Medical College, Rawalpindi from May 2003 to November 2004. A sample of 44 male subjects was selected, comprised of 22 elite endurance athletes (group 1) and 22 age and BMI matched healthy sedentary volunteers as controls (group 2). All those with cardiopulmonary diseases or having family history of these diseases were excluded. M-mode echocardiography was carried out by Toshiba Power Vision 6000 Echocardiograph. Age, weight, height and Body Mass Index were demographic variables while left ventricular end-diastolic internal diameter, diastolic interventricular septal thicknesses, left ventricular posterior wall thickness, and left ventricular mass were research variables. All these data were of ratio type, hence described by mean and standard deviation. The significance of the mean differences for all the variables was derived by applying independent samples student t test. Alpha value of 0.5 was considered as statistically significant. Results: The mean LVIDd was 54.63±1.79 mm, IVST 9.86±0.89 mm, PWTd 8.63±0.73 mm, and LVM 196.36±22.86 gm in athletes and 40.63 2.08, 8.52 0.37, 8.04 0.32, 102.5 11.01 in controls respectively, significantly higher values in athletes. Conclusion: Regular and extensive endurance training results in significantly greater left ventricular mass and volume.