AIM: The aim of this study was to assess relationships between cardiac autonomic regulation after exercise and different types of single-bout exercise of a maximal intensity and of a similar duration. METHODS: The study group consisted of 30 males (23 ± 2 year old), which was separated into three subgroups. Groups A and B performed exercise interventions (continuous or intermittent), while group C represented the control group. Heart rate variability (HRV) was monitored continuously over 30 min after the exercise and consequently during a 6 h period following intervention. Spectral analysis parameters of HRV (total [PT], low- [PLF], high- [PHF] frequency power, LF/HF, and PLF in normalized units [LFnu]) were determined over 5 min intervals. Heart rate recovery (HRR) was also analysed. RESULTS: There were not significant differences between groups A and B for the entire HRV monitoring (P<0.05) or in the relatively expressed HRR. The cardiac autonomic modulation expressed by PT, PLF, and PHF fully recovered in 120 min after exercise, whereas LF/HF and LFnu did not significantly differ (P<0.05) from the control group 60 min earlier. CONCLUSION: Cardiac autonomic recovery after all-out exercise is type non-dependent and sympathovagal balance restores faster than the absolute HRV magnitude.

Ostrava University Human Motion Diagnostic Centre Ostrava Czech Republic