life1life1Heart rate variability, HRV, is the small variation in time between one heartbeat and the next. A heart that varies more from beat to beat is generally under more influence from the parasympathetic nervous system, the rest-and-digest side.
Wearables usually report RMSSD, a statistic of beat-to-beat differences, measured during sleep or at rest. Different devices use different windows and algorithms, so HRV from one brand is not directly comparable with another.
Age, genetics, fitness, sex and the device itself all move the baseline. Two healthy people can have resting HRV values that differ by a factor of three. For that reason the useful comparison is you against your own baseline, not you against a table.
Alcohol, poor sleep, illness, a hard training block and stress commonly lower HRV for a day or more. Consistent sleep, steady training and recovery tend to raise it slowly over weeks. A single low reading rarely means much; a trend is more informative.
HRV is not a diagnosis and not a readiness verdict. It is one input among several. If a wearable reports a persistent change you cannot explain, that is a question for a clinician, not for an app.
In LIFE1. LIFE1 reads HRV from Apple Health or Health Connect and draws it over time exactly as recorded. The Connected devices view shows which device supplied it and when it last synced.
Within one person, a higher trend usually goes with better recovery. Between people, the number itself says little.
Different baselines, and often different devices measuring different windows.
As recorded by your wearable, on a trend line, without thresholds or interpretation.
LIFE1 shows what you measured and what published guidelines say. It does not diagnose, interpret or treat. This page is general information, not medical advice.