Autonomic Heart Rate Regulation During Maximum Incremental Treadmill Test: A Study Case

Background: Street running has been growing exponentially in recent years. It is among the most popular physical activities, according to global data for adults. Having become a popular and accessible sporting event due to the emergence of sports advisors, with increased demand for specialized training in the longer distance run, half marathon and marathon. The HRV analysis is generally used to assess the ANS functioning in cardiovascular research and in different applications related to human well-being. HRV has been used in countless studies, related to cardiovascular research and different applications in human well-being, as an indirect tool to assess the functioning and balance of the ANS and currently rest measures, during exercise, and recovery after exercise have been used for this purpose. Methods: A volunteer who had been running for more than five years and in competitive activity with time less than 20 minutes for 5 km competitions. Male, 29 years old, 64.1 kg, 179.5 cm in height, with no reports of health restrictions such as musculoskeletal injuries and a cardiovascular history diseases or thyroid disorders. The maximum speed test was calculated using the equation correction for incomplete stages proposed by Kuipers (2003). Heart rate was recorded using a POLAR® RS800cx heart rate monitor, with a sampling rate of 1000 Hz. The R-R-interval data recorded by the portable heart monitor was transferred to Polar Pro trainer 5® software. Results: We can observe the variables referring to the autonomic nervous system parasympathetic activity, mean RR, RMSSD and SD1 intervals, as well as the variables used to calculate the sympathetic activity, mean HR, stress index and SD2 for each speed of incremental testing. Conclusion: We conclude that the use of HRV as a tool makes it possible to identify an individual's physical capacity. We also concluded that the HRV variables are sensitive to the physiological changes imposed by the stress of continuous progressive physical exercise, at high exercise intensities the parasympathetic variables PNS, RMSSD, Mean RR and SD1 decrease, as well as SNS, Stress Index and Mean HR that reflects sympathetic activity increase slightly, without achieving complete recovery after 6 minutes post-exercise from baseline.