静力与动力负荷对儿童STI的影响

<正> 近年来,由于无创性测定STI法容易为运动员接受,故作为评定运动员左室功能的良好方法而得到广泛应用。但对于儿童进行不同类型、不同负荷量的体力活动前后STI的变化尚未见报导。本文目的是探讨9-10岁儿童从事静力与动力负荷时STI的变化,为正确组织儿童体育锻炼,促进儿童生长发育提供实验依据。

EFFECTS OF STATIC EXERCISE AND DYNAMIC EXERCISE ON SYSTOLIC TIME INTERVALS (STI) IN CHILDREN

The purpose of this study was to investigate STI changes resulting from static and dynamic exercises in boys, 9-10 years old, so as to reveal the effects of physical work of different types and loads on the heart function.Our research showed that the effects of static load and dynamic load on STI in children were different. After dynamic exercise all items of STI changed significantly and PEP/LVET decreased significantly. No PEP change was found after static exercises (50% and 80% max load). Static exercise of 50% max load resulted in no IVCT change, but static exercise of 80% max load resulted in very significant change of IVCT, and the longest recovery period was found afterwards. Thus, 80% static exercise would result in a heavy, transient heart load in children.Our research also showed that the changes of HR×systolic blood pressure×LVET after dynamic load and static load were significantly different indicating that oxygen consumption in heart muscles was higher during dynamic exercise and the effect of dynamic exercise on heart was stronger.