Effect of long-term soccer training on changes in cardiac function during exercise in elite youth soccer players

<div>It is unclear what the effect of long-term, high-volume soccer training has on left ventricular (LV)</div><div>function during exercise in youth soccer players. This study evaluated changes in LV function during</div><div>submaximal exercise in a group of highly-trained male soccer players (SP) as they transitioned over a</div><div>three-year period from pre-adolescent to adolescent athletes. Data were compared to age-and sex matched recreationally active controls (CON) over the same time period. Twenty-two SP from two</div><div>professional English Premier League youth soccer academies (age: 12.0 ± 0.3 years at start of the</div><div>study) and 15 CON (age: 11.7 ± 0.3 years) were recruited. Two-dimensional echocardiography was</div><div>used to quantify LV function during exercise at the same submaximal metabolic load (approx.</div><div>45%VO2peak) across the 3 years. After controlling for growth and maturation, there were training induced changes and superiority (p<0.001) in cardiac index (QIndex) from year 1 in the SP compared</div><div>to CON. SP (year 1: 6.13 ± 0.76; year 2: 6.94 ± 1.31 and year 3: 7.20 ± 1.81 L/min/m2</div><div>) compared to</div><div>CON (year 1: 5.15 ± 1.12; year 2: 4.67 ± 1.04 and year 3: 5.49 ± 1.06 L/min/m2</div><div>). Similar training induced increases were noted for mitral inflow velocity (E): SP (year 1: 129 ± 12; year 2: 143 ± 16 and</div><div>year 3: 135 ± 18 cm/s) compared to CON (year 1: 113 ± 10; year 2: 111 ± 12 and year 3: 121 ± 9</div><div>cm/s).This study indicated that there was evidence of yearly, training-induced increases in left</div><div>ventricular function during submaximal exercise independent from the influence of growth and</div><div>maturation in elite youth SP</div>