Table 1. Correlation (r) matrix of elite volleyball referees’ cardiac responses with cardiac responses.

	HR pre-match	HR post-match	Ø HR during the match	HRV pre-match	HRV post-match	Ø HRV during the match
HR pre-match	1.00	0.78 ***	0.77 ***	-0.53 ***	-0.42 **	-0.63 ***
HR post-match	0.78 ***	1.00	0.82 ***	-0.46 **	-0.49 ***	-0.59 ***
Ø HR during the match	0.77 ***	0.82 ***	1.00	-0.57 ***	-0.35	-0.72 ***
HRV pre-match	-0.53 ***	-0.46 **	-0.57 ***	1.00	0.81 ***	0.74 ***
HRV post-match	-0.42 **	-0.49 ***	-0.35	0.81 ***	1.00	0.61 ***
Ø HRV during the match	-0.63 ***	-0.59 ***	-0.72 ***	0.74 ***	0.61 ***	1.00

** and *** indicate p < 0.01 and 0.001 respectively.