TRAINING LOAD CONTROL BASED ON THE METHOD OF NONLINEAR ANALYSIS OF HEART RATE VARIABILITY IN FEMALE SKIERS DURING MEDIUM AND HIGH INTENSITY TRAINING

The research purpose is to identify the relationship between intensity threshold values during a test to assess special endurance in elite female skiers, determined by lactate accumulation points using the OBLA method and the multifractal analysis of heart rate variability (DFAa-1), as well as their applied significance in assessing training load in medium and high intensity training.

Methods and organization of the research. The study analyzed lap times, R-R interval recording, HR, lactate values, subjective perception of exertion (RPE) in a stepwise increasing load test on roller skis in a staged control (May, July, October) in 6 elite female skiers. The same indicators were recorded in female skiers during medium and high intensity training from June to October. All data were imported into Kubios HRV Scientific 4.0.1 software (Finland). Load threshold parameters of the load were determined using DFAa-1 = 0.75 for the aerobic threshold and DFAa-1 = 0.5 for the anaerobic threshold. Methods of mathematical statistics were used to analyze the data.

Research results. Strong relationships between DFAa-1 and the indicators in the step test on roller skis were revealed. The dynamics of the decrease in the DFAa-1 indicator with an increase in intensity was shown, reflecting the tension of the regulatory systems both in the step test with increasing load and in training with medium and high intensity.

Conclusion. To use the method of multifractal analysis of heart rate variability in monitoring the training load of medium and high intensity in highly qualified athletes, the determination of individual DFAa-1 threshold values is required. Highly qualified female skiers, when determining threshold values using the lactate accumulation point method, demonstrate an aerobic threshold at the level of DFAa-1 = 0.59, and an anaerobic threshold at DFAa-1 = 0.42.
 

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