Age, Sex & Individual Differences

What is "normal" for HRV differs greatly from person to person. That is why Feelmo looks at your own baseline rather than comparing you with others. This page explains the science, with sources.

It declines with age

HRV tends to decline with age. A study spanning ages 10–99 showed HRV falling across the decades (Umetani et al., 1998).

Figure: an illustration of HRV declining gently with age, with large individual differences (the band width) even at the same age. The figure is illustrative, not actual measurements.

Differences by sex

A study of short-term HRV in healthy people reported that HRV indices differ not only by age but also by sex (Voss et al., 2015). HRV norms differ by age group and sex (Shaffer & Ginsberg, 2017).

So, "compare with yourself"

• The same score means different things at 20 and at 60. Whether you're higher or lower than the person next to you means little
• What is meaningful is change from your own baseline. Feelmo always recommends "comparison with yourself" precisely because these individual differences are large (Umetani et al., 1998; Voss et al., 2015)

How Feelmo handles it

Given these large individual differences, Feelmo reads HRV against your own baseline. How metrics are integrated is the core of Lumo Core and is not disclosed, as a trade secret. Related: Regulation Score · Heart Rate & Resting Heart Rate.

References

1. Umetani K, Singer DH, McCraty R, Atkinson M. Twenty-four hour time domain heart rate variability and heart rate: relations to age and gender over nine decades. Journal of the American College of Cardiology. 1998;31(3):593–601.
2. Voss A, Schroeder R, Heitmann A, Peters A, Perz S. Short-term heart rate variability—influence of gender and age in healthy subjects. PLoS One. 2015;10(3):e0118308.
3. Shaffer F, Ginsberg JP. An Overview of Heart Rate Variability Metrics and Norms. Frontiers in Public Health. 2017;5:258.