Table 1: Listed are the Lower Limits of Normal for Each Parameter of HRV Corresponding to the Three Different Age Groups. Max/min During Deep Respiration and the Posture Index, which do not Significantly Contribute to Normal Data, are Marked in Grey

Age n DR: VC DR: RMSSD DR: max-min VR Rest: VC Rest: RMSSD DR: max/minn PI
<40 96 4.63 21.03 87.20 1.36 3.57 16.27 1.11 1.06
40-60 71 3.10 12.88 46.00 1.19 2.37 11.29 1.05 1.06
>60 23 2.13 7.24 25.40 1.13 1.40 8.97 1.03 1.03

DR = deep respiration; VM = valsalva manoeuvre; Rest = HRV at rest; PI = posture index , VC = coefficient of variation; RMSSD = root mean square of successive differences.