Abstract

The health condition of Estonian children raises some concern. The problem is acute in children who are engaged in sports: there have been cases of sudden death during physical activity, and there is the danger of exceeding recommended physical loads.
AIM. The aim of the study was to find out changes in ECG at rest and to assess changes in ECG registered during exercise test in 10–17-year-old children.
METHODS. Altogether 738 boys and 646 girls, aged 7–17 years, who were engaged in sports and had 1 to 11 years of training experience were selected for the study. The GE Medical Systems IT Cardiosoft (Germany) was used to register ECG. Step-wise increasing loads on an ergometer (eBike Basic/Comfort, Germany) were used for the exercise test  with a step length of 3 minutes and an effort of 1, 2 and 3 W/kg.
RESULTS. We observed frequent changes in ECG at rest before the test in children engaged in sports, which can be attributed to a weakened health condition and partly to high exercise loads. We noted an increase in the rate of disturbances in the repolarisation process under the influence of the physical load, especially in girls. This suggests that processes of adaptation to physical loads are not adequate and that overloading is still going on.
CONCLUSION. The results of the study show that it is necessary to establish normative values for changes in ECG registered during the exercise test in children engaged in sports.