Purpose. To investigate the cardiovascular system at rest and during bicycle exercise in relation to peak height velocity, 41 boys and 45 girls aged 7–16 were studied annually for 10 years. Basic procedures. Measurements of systolic blood pressure (SBP) and diastolic blood pressure (DBP), systolic volume (SV), cardiac output (CO), cardiac output per kg body weight (COkg), heart rate (HR), left ventricular ejection time (LVET), mean systolic ejection rate (MSER), peripheral resistance (PR) were made at rest and during bicycle exercise and expressed at yearly intervals at a range from –3 to +3 years from age at the peak height velocity (PHV) of each individual. Main findings. The results showed a mean PHV of 8.2 ± 2.2 cm ∙ yr–1 in girls and of 9.7 ± 2.3 cm ∙ yr–1 in boys. PHV occurred on the average at ages 12.2 in girls and at 13.7 in boys. According to age at PHV schoolchildren were div ided into early, mid and late maturers. With increasing maturation there appeared a progressive increase in systolic and diastolic blood pressure and a decrease in HR, COkg, PR. Increase in SV before PHV in girls and in PHV in boys resulted in more intensive increase in MSER. Small changes in parameters of sphygmogramms from arteries characterized stable capacity of the arterial tree to receive blood pumped with each heart contraction. Conclusions. Adaptive cardiovascular response to standardized exercise and to incremental power output in the bicycle test r ev ealed gender d ifferences and r eflected increased contractility o f myocardium and e ffectiv eness of c ardiov ascular control during the maturation process. Boys had higher values for SV, MSER and lower values for COkg. Late maturers at every stage of growth till and at PHV had a more effective pattern of cardiovascular response to bicycle exercise when compared with mid/early maturers.
Key words: growth, maturation, cardiovascular system, exercise