Gender Differences in Heart Rhythm Normalization in Young Sportsman After Test Physical Activities

Abstract

Aim. To find gender differences in the heart rate normalization of young athletes in the rapid phase of recovery after test physical activities. Materials and methods. In 60 young biathletes and skiers of 13-18 years old (33 boys and 27 girls) were studied indices of heart rate normalization, heart rate variability calculated by the exponential equation depending on sex. Comparison of the results was carried out after sub-maximum cycle ergometric loads of 2.5 W/kg carried out during 3 min and loads until the work was done, dosed to 1 kgof body weight (4 W/kg for boys and 3.5 W/kg for girls). Load testing was performed in a sitting position on a «Lode» ergometer (Netherlands)with continuous recording of spiro ergometric indices on «Cortex» system and each heart cycle duration on «Polar RS800»system. The maximum mechanical performance was calculated using the Mueller equation in 0.5 and 6 minutes. We determined: HPI values when performing test physical exercises in young men and women; anaerobic (PWCmx0.5) and aerobic capabilities (PWCmx6)of young athletes depending on gender. Results. Analysis of the heart rate in boys and girls in the phase of rapid recovery after the test physical activity was showed that after sub-maximum load, dosed per kilogram of body weight of boys have an advantage in the nature of normalization of the heart rate.They have a higher rate of HRV reduction in relative terms, given the potential for heart rate reduction; faster recovery of HRV; indicators of the exponential equation (large residual dispersion of its ratio to total dispersion, lower values of multiple correlation coefficient in young men) also indicate their advantage in the nature of recovery. After performing the load before the refusal of work was not determined by gender differences in not one of the indicators of heart rate normalization in the phase of rapid recovery. Conclusions: boys have higher rate of HRV reduction in relative values, taking into account potential heart rate reduction; faster HRV recovery; exponential equation indices (higher residual dispersion of its ratio to total dispersion, lower values of multiple correlation coefficient) also indicate the advantage of boys in character of recovery after sub-maximum load. More frequent heart rate and more pronounced reduction of HRV in girls, at the end of sub-maximum load, and slower normalization of different heart rates indices are associated with lower aerobic performance capabilities. No gender differences were identified in anyof the heart rate normalization rates during the rapid recovery phase after the pre-dropout phase.