In the submitted study the authors evaluated the effect of regular physical activity on the development of autonomous regulation of the circulation in children who had previously treatment on account of a malignant tumour, in particular leukaemia, and were treated with cardiotoxic anthracyclines. In 22 children (9 - 21) with a history of leukaemia the authors recorded by non-invasive methods the pulse rateat rest, pulse intervals (PI), systolic (BPs) and diastolic (BPd) blood pressure and calculated the baroreflex sensitivity of the heart (BRS in ms*mmHg -1 , BRSf in Hz*mmHg -1 ). The childrens physical activity was assessed for one month by means of questionnaires and the approximate value of expended energy was expressed in kJ/kg/day. The authors calculated mean values, standard deviations and mutual correlation coefficients of these variables: age, TI, BPs, BPd, BRS, BRSf, body weight, height, energy expenditure in kJ/kg/day and the body mass index, BMI. By regression analysis they assessed the statistical significance of difference in the development of different circulatory parameters and indices of somatic development with regard to age and therapeutic procedure in children treated with anthracyclines and those not treated with anthracyclines. The rise of BPs and BPd correlates with age, it does not correlate with the mean physical load. The mean length of TI correlates with age and the mean physical load. BRS correlates with TI, BRSf correlates with BMI. In the group of children treated with anthracyclines there is a more rapid prolongation of TI, rise of BRS, but a slower rise of BPs, BPd, body weight, BMI and physical activity as compared with the group not treated with anthracyc- lines. The trend of BRSf is not influenced by anthracyclines. Anthracycline treatment interferes with the development of cardiovascular functions. The more rapid prolon- gation of TI and the slower rise of BP with age in these children is not associated with regular physical activity.

        Key words: leukaemia, anthracycline therapy, baroreflex, physical activity