Children’s sports have continued to become more competitive in recent decades, with athletes taking on more intense training at earlier ages. A research team from Italy examined the impact of endurance on cardiac remodeling, specifically in the heart’s right ventricle (RV).

Lead researcher Flavio D’Ascenzi of the University of Siena in Italy and colleagues published the findings in the June issue of the International Journal of Cardiology.

“Although the number of children involved in sports activity programs is increasing and there is a trend to more intensively engage very young individuals in competitive events, [little information is] currently available on the consequences of intensive exercise conditioning on cardiac remodeling and function,” he and colleagues wrote.

The study examined 62 pre-adolescent swimmers between the ages of 9 and 13 years old. Additionally, 37 sedentary boys were matched to the participants as controls. The 99 participants underwent physical examinations and echocardiography twice, once at the study onset and then six months later to see the impact of such conditioning.

Researchers found that RV growth occurred in both the athletes and control subjects, but the amount of RV growth was significantly higher among the swimmers. Comparatively, the athletes had greater increases in right ventricle outflow tract, end-diastolic and end-systolic areas.

“The RV dilatation was accompanied by a significant increase in functional parameters … with global RV strain and RV [fractional area change] remaining stable,” the authors wrote. “These findings support the hypothesis that RV function is not impaired by endurance training in the early phase of the sports career of an athlete.”