Fig. 6

The box plot of SD1 Poincaré, alpha 1 of DFA, and spectral entropy in the men and women and in three phases of the test. *, the significance between rest and recovery; #, the significance between rest and stress condition; +, the significance between stress condition and recovery; †, the significance between men and women. Alpha 1 of DFA index increased after stress and recovery only in women (between rest and recovery: Z of Wilcoxon’s test = − 2. 9, p < 0.004; between stress and recovery: Z of Wilcoxon’s test = − 2. 27, p < 0.02). There was no significant difference between genders