Эффективность кардиобиоуправления у подростков 15–16 лет после физической нагрузки в условиях низких температур

Abstract

Short-term biofeedback (BF) training provides effective restoration of the cardiovascular system (CVS) after physical exercise. Purpose: assessment of CVS reactivity in adolescents aged 15–16 years during a heart rate variability (HRV) BF session following a speed-strength exercise (thricerepeated standing long jump) in the open air (from –1 to –10 °C). Materials and methods. Healthy adolescents were examined: an experimental group (n = 15) subject to HRV BF training (3 min) using Varikard equipment (Ramena, Russia) in order to increase the total HRV power and a control group (n = 12). The following stages of recording HRV and blood pressure indicators were singled out: background (initial indicators), period immediately after physical activity, and recovery period with HRV training (experimental group) or being at rest (control group). Results. During the recovery period after a HRV BF session, subjects from the experimental group showed significantly higher total HRV power compared with the control (p = 0.04). In experimental group individuals with a heart rate of less than 90 bpm against the background of its increase during BF training, stress index did not change significantly. In subjects with tachycardia (above 90 bpm), heart rate and stress index remained elevated at all stages. Conclusion. Short-term BF training (3 min) after a speed-strength exercise in a cold environment increases the total HRV power in adolescents; the degree of reduction in sympathetic response depends on the initial heart rate level. The relative increase in heart rate during HRV BF training after physical exercise in a cold environment indicates the need for a longer BF session (over 3 min) in order to achieve a more pronounced influence of vagal effects on the heart rhythm.