The Effect of Training Experience on Cardiac Morphology in Resistance Exercise Practitioners: A Study on Left Ventricular Systolic and Diastolic Parameters and Left Atrium Mechanical Functions

<i>Background and Objectives</i>: Resistance exercises (REs) are a type of physical activity that individuals from many age groups have been doing recreationally, both as amateurs and professionally, in their daily lives in recent years. It is crucial to understand the effects of such sports on cardiac morphology in order to maximize the benefit of training and to tailor the training content accordingly. The aim of this study was to investigate the relationship between training experience (TE) and left ventricular (LV) systolic and diastolic parameters and left atrial (LA) mechanical function in healthy subjects who regularly performed RE for different durations. <i>Materials and Methods</i>: Forty-five healthy adults [age = 28.91 ± 10.30 years, height = 178.37 ± 5.49 cm, weight = 83.15 ± 13.91 kg, body mass index = 26.03 ± 3.42 kg/m², TE = 7.28 ± 6.49 years] who performed RE between 1 year and 20 years were included in our study. The transthoracic echocardiograms (ECHOs) of the participants were evaluated by the cross-sectional research method, which is often used to understand the current situation in a given time period. Correlations between TE and LV systolic and diastolic parameters and LA mechanical function were analyzed. <i>Results</i>: As a result, interventricular septal thickness (IVS; r = 0.33, <i>p</i> = 0.028), the aortic diameter systole (ADs; r = 0.56, <i>p</i> < 0.001), and aortic diameter diastole (ADd; r = 0.58, <i>p</i> < 0.001) were positively correlated with TE, indicating associations with increased left ventricular (LV) hypertrophy and reduced ventricular compliance, while the aortic strain (AS; r = -0.44, <i>p</i> = 0.002), aortic distensibility (AD; r = -0.62, <i>p</i> < 0.001), and diastolic flow parameters including E (r = -0.41, <i>p</i> = 0.005), E/A (r = -0.38, <i>p</i> = 0.011), and E/Em (r = -0.31, <i>p</i> = 0.041) were negatively correlated with TE, reflecting impairments in diastolic function. <i>Conclusions</i>: This study showed that diastolic parameters were adversely affected in chronic RE. Therefore, we think that these individuals may have decreased relaxation and filling functions of the heart, which may also reduce adequate oxygen and nutrient delivery to the tissues. In this context, cohort studies are needed to analyze in detail the reasons for the decrease in diastolic parameters in these individuals.