Long-Term Monitoring of Physical Behavior Reveals Different Cardiac Responses to Physical Activity among Subjects with and without Chronic Neck Pain

Table 3

Results from the repeated measures ANOVAs of heart rate variability indices. -values and values are shown for the effects of activity type, location and group, and their interactions.

Variable		Main effects						Interaction effects
		Activity		Location		Group		Activity × group		Location × group		Activity × location × group
		IBI (ms)	49	213.6	<.0001	9.2	<.0001	5.1	.03	3.2	.07	1.4	.26	0.7	NS
RMSSD (ms)	49	37.0	<.0001	4.8	.01	3.8	.06	1.9	.16	0.9	NS	0.3	NS
LF/HF (ms)	42	18.4	<.001	0.1	NS	2.6	.11	7.6	.001	2.2	.12	0.2	NS

Note: nonsignificant, NS, ; all models are adjusted for type of work.
IBIs, interbeat intervals; RMSSD, root mean square of successive differences between interbeat intervals; LF/HF, ratio between low- and high-frequency spectral power of heart rate variability.