What does HRV readiness actually measure?

HRV reflects the balance of your autonomic nervous system. A reading near or above your personal baseline suggests good parasympathetic recovery and readiness to train hard, while a meaningful drop suggests accumulated fatigue, illness, or stress that warrants an easier day.

Why compare to a rolling baseline instead of a fixed target?

HRV is highly individual and drifts with fitness, so absolute numbers mean little. What matters is today's deviation from your own recent normal. A 7-day rolling average smooths daily noise and gives a fair reference point.

What is the normal range method?

It builds a band around your baseline using the variability of your own readings. If you do not supply a standard deviation, the tool assumes a typical coefficient of variation of about 6 percent. Readings inside the band are normal; outside it signal a real change.

How should I act on a low reading?

A single low reading can be noise, but a clear drop below your normal band — especially several days running — is a cue to reduce volume or intensity, prioritise sleep, and check for illness. Pushing hard against suppressed HRV often deepens fatigue.

When should I take the reading?

Consistency matters more than timing. Measure first thing after waking, in the same position (lying or seated), before caffeine or hard movement, every day. Erratic timing adds noise that swamps the genuine recovery signal.

HRV Readiness Score Interpreter

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Heart-rate variability is one of the best daily windows into recovery, but raw numbers are meaningless without your personal context. This tool compares today’s reading to your 7-day rolling baseline and turns the deviation into a clear train-hard, hold, or ease recommendation.

How it works

The tool builds a normal band around your baseline using the variability of your own readings:

band width  = baseline × coefficient of variation (default ~6%)
deviation   = (today − baseline) / band width      (in standard deviations)

If you supply a standard deviation, it is used directly; otherwise a typical 6 percent coefficient of variation is assumed. A reading well below the band signals suppressed recovery and an easier day; near or above baseline signals readiness to train as planned or push.

Notes

One low reading can be measurement noise — trends over several days matter more than any single morning. Always measure at the same time, position, and conditions. HRV guidance complements, but does not replace, how you actually feel and your coach’s plan.