A Consecutive Study of Some Electrocard ogramVariables of during Applying Aerobic Stress to (11-12) Years Old Children

Abstract

Exploring the effect and immediate response of standard aerobic stress in the circulatory system dynamic variables, and recognizing their values at rest, during and directly after aerobic stress in healthy children (11-12) are obviously necessary to reach a scientific basis. The exercises and training modules will be built on such a basis in concord with the children's abilities through discovering and comparing the research variables. Moreover, the results of these studies are part of the basis that is necessary for any sports field work. This agrees with the experts and other concerned views that high sports levels require for physical, skill, and physiological preparation. This study aims to: recognize the values of some physiological variables before, during aerobic stress in (11-12) years old children. Also to discover the different values of the physiological variables between the different measure stages in (11-12) years old children.. To validate the research hypotheses, the researcher used the descriptive method for being suitable to the research methodology. The samples was randomly selected and included (30) male pupils from Bilal Al-Habashi and Al-Muthanna primary schools in Mosul. The researchers used Bruce test for aerobic stress and body measurements to collect data. Some variables were taken as vital indicators for the adequate functioning of the cardio-circulatory system. The variables covered some variables were related to the electrocardiogram (ECG) such as: Heart Rate (HR), Left Ventricular Hypertrophy (LVH),RightVentricularHypertrophy (RVH), QRS Interval,S-T Interval,Q-T Interval, P-R Interval, P-R Segment, T-wave and Heart Axis. To validate the study aims, the researchers applied Bruce test for aerobic stress in all the subjects between (24/3/2008 to 2/4/2008). The researchers used the following statistical tools: (Arithmetic Mean, Standard Deviation, Coefficient of Variation "C.V", Paired- Sample t-test and Relative Change Equation). It is concluded that there is clear increase of HR over the different measure stages of the aerobic stress. And there is more evident decrease of the Diastolic duration than the Systolic duration in successive stress stages, expressed by the variables of the ECG measurements. And there is more increase in the right ventricle' voltage than the that of the left ventricle, especially in the intermediate stage of the consecutive test, although there are no obvious differences in the heart voltage values throughout the variables (LHV, RVH and T-Wave). Finally, although there are no obvious differences in Heart Axis, there is a simple rightward deviation of the heart axis to the intermediate stage of the consecutive test, and up to normalcy at the final stages of the consecutive test.