Table 2. Chronic and acute frequency-domain HRV data for the three groups, shown as mean and standard deviation collected pre and post-intervention.

	Mindfulness group	Music group	Control group
Chronic HRV variables:
Daytime:
HF baseline	3.4 ± 2.5	2.8 ± 2.5	2.7 ± 2.9
HF post	4.3 ± 2.8	3.2 ± 2.1	3.5 ± 2.7
LF/HF ratio baseline	3.2 ± 2.6	3.3 ± 2.6	2.4 ± 2.7
LF/HF ratio post	2.6 ± 2.4	2.6 ± 2.2	2.9 ± 3.2
Nighttime:
HF baseline	4.2 ± 1.8	3.8 ± 2.1	3.9. ± 2.4
HF post	4.9 ± 2.1	4.3 ± 2.4	4.5. ± 2.5
LF/HF ratio baseline	2.8. ± 1.8	2.7. ± 2.2	2.8. ± 2.3
LF/HF ratio post	2.2 ± 1.9	2.5. ± 2.1.	2.6 ± 2.2
Acute HRV variables:
HF-HRV*	4.4 ± 1.9	3.8 ± 2.5	-
LF/HF ratio*	1.4 ± 1.3	2.6 ± 3.0	-

* Mean across the 10-day intervention.

Acute data was not collected for the control group.