Change in the functional status of extreme athletes in response to adverse environmental conditions

Aim: the authors aim to develop criteria for assessing the functional status of extreme athletes in response to adverse environmental conditions by using the data obtained from the circulatory and autonomic nervous systems. Materials and methods: the study included 60 extreme athletes (mean age 25.1 ± 3.1 years). Heart rate variability (HRV) measurements were performed with the Varicard 2.51 system and used for assessing the functional status of athletes. The statistical analysis was performed with STATISTICA 7.0 software. Results: based on HRV data, it was demonstrated that heart rate (HR), mean and maximum RR intervals (Mean RR and XMax), the percentage of successive RR intervals that differed by more than 50 ms (pNN50), the mode (Mo), the amplitude of the mode (AMo50), and the stress index (Si) of the regulatory systems could be used for assessing the functional status of extreme athletes in response to adverse environmental conditions (p 0.70; r > -0.70) with the functional status of extreme athletes.