The Effect of Swimming Training on Heart Structure and Function of Elite Athletes

Introduction: Swimming training fosters the heart performance.The aim of this study was to determine the effect of swimming training on heart structure and function of elite swimmers. Methods: The study was a causal comparative. The statistical sample included swimmer and nonathlete groups. Athletes were the elite swimmers who participated voluntarily in this study. Inclusion criteria for athletes included a history of at least 5 years of regular swimming training. After sampling, all participants took part in the echoheart test in which they were given Color Doppler MMode echocardiography. The functional and structural parameters included left ventricular internal diameter in systole (LVIDs), left ventricular internal diameter in diastole (LVIDd), interventricular septal end diastole (IVSd), left ventricular mass index(LVMI), left atrial dimensions (LAD), aortic root dimension (ARD), left ventricular posterior wall dimensions (LVPWD), heart rate (HR) and ejection fraction(EF).ShapiroWilk test was used to normalize the research data. Statistical analysis was used by independent samples ttest and Analysis of variance (ANOVA). The pvalue was defined as p ≤ 0.05. The hypothesis test was performed using SPSS software version 19. Results: The independent sample ttest results showed that swimmers had a significant decrease in LVIDs(p = 0.001), LVPWD(p = 0.001) and HR(p = 0.001) compared to nonathletes. The results also revealed that swimmers had a significant increase in a LVIDd(p = 0.001), LAD(p = 0.001), ARD(p = 0.001) and EF(p = 0.012) compared to nonathletes.There was no significant difference between groups in IVSd(p = 0.789) and LVMI(p = 0.931). But the results were fifferent when variables were adjusted to the participants’ age, weight, height and body mass index (BMI) by ANOVA. The adjusted results showed that swimmers had a significant decrease in LVIDs(p = 0.002) and HR(p = 0.019) compared to nonathletes. The results also revealed that swimmers had a significant increase in a LAD(p = 0.001) and ARD(p = 0.001) compared to nonathletes.There was no significant difference between groups in LVIDd (p = 0.266), IVSd (p = 0.255), LVMI (p = 0.984), LVPWD (p = 0.128), and EF (p = 0.063). Conclusion: Longterm swimming training can lead to some heart physiological changes in elite swimmers. It seems that this changes can improve heart performance in this athletes.