Non-invasive assessment of short and ultra-short heart rate variability during different physical and physiological tests

Themain aim of the present study was to determine the short- and ultra-short-term heartrate variability (HRV) during different physical and physiological tests and tocompare HRV to different performance levels. The latter aim was to compareparticipants’ short- and ultra-short-term heart rate variabilitybefore-during-post-tests. Our hypothesis was that there would be a significantdifference between test performance and HRV parameters, and the high performinggroup would have significantly higher HRV parameters than the low performing group.Fifty-three healthy men (M age =26.9±4 years, M height =177.9±5.7cm; M weight =77.8±8.7kg) were recruited in the current study. We completed the data collectionprocedure for each participant in four consecutive days. On day-1, anthropometricmeasurements were conducted and then participants performed isokinetic tests. Onday-2, participants performed anaerobic tests; on day-3 equilibrium tests, and onday-4 aerobic capacity tests. The HRV records of all participants were obtainedbefore, during and after all these tests. Based on the participants’performance, they were divided into two groups: participants in G1 had lowerperformance and those in G2 higher performance. A two-way repeated measures ANOVAyielded significant differences in HRV values obtained in the four differenttests. There was a significant difference between fitness test performance andthe variation of short- and ultra-short-term HRV parameters. Also, significantdifferences in HRV values before, during, and after the testing were observed.