Table 3: Differences in the effect of blue and red light on HRV measurements between SVT, heart failure (CHF) patients and athletes.

		Effect of red light			Effect of blue light
		SVT	CHF	athletes	SVT	CHF	athletes
short-term HRV measurements (@ 10min exposure)	SDNN (ms)	+31,2	+13,3	+59,0 *	+11,8	+17,3	+36,3 *
	RMSSD (ms)	+12,0	+16,7	+29,5 *	+11,0	-4,1	+22,7 *
	pNN50 (%)	+4,8	-0,1	+10,7 *	+7,7	+3,2	+8,5
	LF/HF	-0,4	+0,6	+0,1	+4,9 *	+0,6	-0,1
	SD 1 (ms)	+8,5	+11,9	+20,9 *	+7,8	-0,1	+16,1 *
24 hrs Holter HRV measurements	SDNN (ms)	+7,9	+6,6	+27,7 *	+8,6	+8,5	+37,3 *
	RMSSD (ms)	+4,0	+1,6	+6,6	+3,7	+6,3	+21,7
	pNN50 (%)	+2,4	+1,6	+2,3	+2,8	+2,3	+5,3
	SDSD (ms)	+2,9	+1,0	+6,7	+2,5	+5,4	+16,5

values are given as Δ mean (red light or blue light minus preceding neutral light); SDNN: standard deviation of RR-intervals (ms); RMSSD: square root of mean squared difference of successive RR-intervals (ms); pNN50 percentage of heart beats over 50 ms from the baseline (%); LF/HF: ratio of low to high frequency RR-variation calculated by power spectral density analysis; SD1: standard deviation of the scatter away from the 45 degree line in the Pointcaré plot (ms); SDSD: standard deviation of the successive difference between adjacent R-R intervals (ms); * p<0,05 for differences between groups.