Table 2

Mean values, coefficients of variations, and correlation coefficients of ln transformed heart rate variation indices in 70 kibbutz members recorded two months apart             

Sample mean
(n = 70)
Coefficient of variation (%)
(n = 70)
Correlation coefficient
(n = 70)
(n = 32)
(n = 38)
pAge < 50
(n = 45)
Age ⩾ 50
(n = 25)
SDFree3.636.00.770.710.83NS0.790.74 NS
Metronome3.596.10.780.660.84NS0.750.78 NS
RMSSDFree3.298.00.750.660.79NS0.830.62 NS
Metronome3.297.40.780.590.86 < 0.050.810.73 NS
Area very lowFree5.459.00.650.560.73NS0.700.60 NS
Metronome5.279.70.640.610.68NS0.630.66 NS
Area lowFree5.3011.50.680.690.70NS0.620.70 NS
Metronome4.9510.70.750.770.72NS0.660.79 NS
Area highFree4.9512.10.760.740.78NS0.800.69 NS
Metronome5.1110.50.820.720.87NS0.840.80 NS
Total PSFree6.457.00.770.710.83NS0.780.74 NS
Metronome6.336.70.800.720.84NS0.770.82 NS
  • SD, standard deviation of RR interval; RMSSD, root mean square of differences of successive RRs; area very low, the area at very low frequency (0.0033 to < 0.04 Hz); area low, the area at low frequency (0.04 to < 0.15 Hz); area high, the area at high frequency (0.15 to < 0.40 Hz); total PS, total power spectrum (0.0033 to < 0.40 Hz).

  • The values for the SD and RMSSD are in ms and the values for the areas and total power are in ms2.

  • Correlation coefficient measured as between subject variability expressed as percentage of total variability.

  • 69 cases were included for metronomic breathing.