Table 2. Fetal HR and HRV metrics fitted by the mixed models.

	Exercise vs. Control			Apnea vs. Breathing			Group-by-condition
	Estimate	SE	p†	Estimate	SE	P†	Estimate	SE	p†
Epoch Duration (sec)	15.8	7.86	0.062	−0.94	0.41	0.13	0.97	0.59	0.11
Log HF	0.81	0.25	0.028	−1.40	0.21	<0001	0.65	0.29	0.033
Log RSA	0.64	0.27	0.11	−1.17	0.21	<.0001	0.52	0.30	0.09
Log RMSSD	0.34	0.14	0.077	−0.49	0.10	<.0001	0.22	0.14	0.11
Log HRV	1.28	0.37	0.013	0.06	0.33	0.016	1.06	0.46	0.029
Log Total Power	1.06	0.36	0.057	−0.34	0.30	0.62	0.96	0.42	0.029
Log VLF	1.25	0.45	0.064	−0.003	0.42	0.057	1.18	0.59	0.056
LogLF	1.01	0.46	0.069	−0.37	0.35	0.74	0.58	0.49	0.25
Log INT	1.22	0.42	0.032	−1.05	0.32	0.009	0.83	0.45	0.078
IBI (msec)	33.6	10.5	0.008	−27.8	5.22	<.0001	10.7	7.40	0.16
HR(bpm)	−10.3	3.50	0.01	8.68	1.65	<0001	2.36	2.33	0.32
Log VLF/LF	0.24	0.41	0.96	0.37	0.41	0.038	0,51	0.58	0.38
Log VLF/HF	0.59	0.46	0.48	1.40	0.46	<0001	0.70	0.65	0.29
Log LF/HF	0.20	0.37	0.55	1.02	0.31	<0001	0.05	0.44	0.92

^†based on Type 3 tests for the fixed effects

^‡mixed models include random intercepts only