Vegetacinių sistemų rodikliai kartotinio nuosekliai didinamo krūvio metu po anaerobinio prieškrūvio

This study was aimed to determine the influence of prior anaerobic load on the cardiorespiratory system and blood lactate parameters during intermittent increasing cycling exercise. Seven female students from the Lithuanian Academy of Physical Education (age — 22.1 (1.5) years, height — 169.2 (6.6) cm, weight — 57.7 (5.1) kg, maximal oxygen consumption — 41.9 (5.2) ml·kg·min) performed the continuous increasing test until exhaustion and two intermittent increasing tests (IT) on Monark ergometer. One of the IT was conducted 15 min after maximal anaerobic 30 s load (MAL), e.g. under conditions of metabolic acidosis. Pulmonary gas exchange was measured breath-by-breath throughout all tests. Maximal oxygen consumption ( ̊ VO2max) was determined as the highest value in 20 s period before the subjects’ volitional termination of the continuous increasing test. The heart rate (HR) was continuously recorded using „Polar S810“ HR monitor (Finland). Blood samples were collected from the fi nger tip for immediate analysis of blood lactate concentration („Eksan-G“, Kulis et al., 1988). The samples were taken before and at the end of each load phase of IT. The dynamics of blood lactate (La) concentration during IT was changed after MAL. After decreasing at initial loads (before test 7.83 (1.36); 17 W — 6.05 (1.49); 50 W — 4.47 (1.36); 75 W — 3.18 (1.15); 100 W — 3.08 (1.08) mmol / l), it started increasing at the intensities near the lactate threshold (125 W — 3,92 (1,26) mmol / l; 150 W — 5,19 (1,59) mmol / l). Under both conditions the HR was linearly increasing as the function of work intensity, but was signifi cantly higher at lower intensities after MAL. The values of peak end tidal CO2 pressure (PETCO2) were signifi cantly decreased at all intensities in comparison with control values. The dynamics and values of oxygen uptake, CO2 output and pulmonary ventilation did not signifi cantly change under conditions of metabolic acidosis.