Efeito de uma prova de triathlon na variabilidade da frequência cardíaca em atletas amadores

Abstract

The aim of the present study was describe the effect of a triathlon event on heart rate variability (HRV) in its time domain as biofeedback mechanism in seventeen amateur athletes (38,8 ± 7,8 yrs.; 175,9 ± 6,7 cm; 77,4 ± 8,6 kg) of a triathlon team who had their HRV indexes obtained immediately prior and after the end of an event as part of the national calendar. This research had an ex-post facto design and used the descriptive statistic of central and variability tendency demonstrated as mean and standard deviation and inferential analysis through paired t test to comparisons pre and post event (p<0,05). Mean values before (PRE) and after (POST) the event were, respectively: SDNN 74,23 ms (± 47,05 ms) and 32,10 ms (± 12,92 ms; ∆ -56,75%), RMSSD 42,30 ms (± 39,26 ms) and 20,01 ms (± 11,21 ms; ∆ -52,69%), pNN50 14,33 % (± 17,19 %) and 3,63 % (± 4,48 %; ∆ -74,61%), MEANRR 863,43 ms (± 182,45 ms) and 691,70 ms (± 117,10 ms; ∆ -19,84%) and MEANHR 74,24 bpm (± 18,85 bpm) and 89,52 bpm (± 16,46 bpm; ∆ 20,58%). All analysed parameters changed significantly, indicating that a triathlon event alters the balance in the autonomic nervous system through the HRV in its time domain.