Table 4.

Change in Each Variable of the HRV Analysis Among MI Subjects (n=35)

	Rest	Warm‐Up	Warm‐Up—VT	VT—Peak	Recovery	P Value
HF, ms2	60.3±57.6	54.5±62.1	28.7±32.7	3.3±6.9	23.1±37.1	<0.001
LF, ms2	115.9±145.1	105.4±134.8	47.3±66.9	7.6±10.8	45.3±85.2	<0.001
L/H	3.8±4.6	4.5±5.1	5.0±4.8	6.1±3.6	6.8±4.5	0.004
CVRR, %	2.5±0.9	2.9±1.0	2.1±0.7	1.7±0.4	2.9±0.9	<0.001

The data were compared using a mixed‐effect model. CVRR indicates coefficient of variation of RR intervals; HF, high‐frequency component; HRV, heart rate variability; L/H, ratio of LF and HF; LF, low‐frequency component; MI, myocardial infarction; VT, ventilator threshold.