The effects of one course of endurance training on functional and structural indices of the heart in children
Background: The strenuous and perseverant exercises have profound effects on the functional and structural status of the heart in children. The goal of this study was to determine the effects of the above mentioned exercices on some cardiac indices such as stroke volume(SV), cardiac output(CO), left ventricle ejection fraction(LVEF), left ventricle end-diastolic diameter(LVEDd), left ventricle end-diastolic volume(LVEDV), left ventricle mass(LV mass), and left ventricle posterior wall diameter(LVPWd). Methods: The study was done on 20 children(10 patients as the case and 10 ones as the control groups), having the average age, height and weight of 10.8+/- 6yr, 149 cm and 36+/- 8 Kg, respectively. The case group had a perseverant running three times a week for 12 weeks, reaching 50-70% of their maximal heart rate. In the both groups, all the above mentioned indices were measured before the study, by echocardiography. Again, all the parameters were measured 12 weeks after the perseverant running. Conclusion: The results of the study showed no significant difference between the case and control (without exercises) groups who had increased their SV index by 5.3 and 1.37%, respectively. The CO index with an increase by 7.29 and a decrease by 6.9 in the case and control groups, respectively, also showed no significant difference. Also LVEF displayed no significant difference in none of the groups with( the case) and without( the control) exercises. LVPWd showed an increase by 2.14 & 2.17 in the case and control groups, respectively, which indicated no significant difference. Neither LVEDd nor LV mass didn’t show any significant difference in the control group, with a decrease by 2.26 and 0.31, respectively. Meanwhile, the case group demonstrated a significant difference in the latter indices, with an increase by 6.78(P value<0.023) & 12.64(0.003), respectively. Finally LVEDV showed a significant difference with an increase by 24.7(P value<0.002), in the case and no significant difference with an increase by 2.29 in the control groups, respectively.