What’s new
Normalized HRV still predicts what your HRV should be at this morning’s resting heart rate and reports how far today sits from that. What changed is how that percentage is classified. The old fixed bands (±5%, ±12%, ±20%) and cause-naming labels (Stressed, Fatigued, Unusual) are gone. States are now measured in your own variability — the standard deviation of your recent readings around the fitted line — and describe only the observation: Strongly Suppressed, Suppressed, Slightly Suppressed, Balanced, Slightly Elevated, Elevated, Strongly Elevated. Balanced is within half a standard deviation of expected: your usual range.
The detail view is new on both platforms. Where Today Sits is a scale split at the state cut-offs, with your usual range shaded, today’s marker in its state color, and every cut-off labelled with your own percentage. How It’s Classified translates each state into personal numbers, which are asymmetric on purpose (one standard deviation below expected is a smaller drop than one above is a rise). While Tempo collects the 30 days of paired resting heart rate and HRV it needs, the badge reads Calibrating and the view shows progress under Learning your usual range.
Connected AI assistants now receive the state, your usual range and a 7-day trend in the same units in wellness data over MCP.
Why it helps
Day-to-day HRV noise varies enormously between people, so a fixed percentage band cannot know how noisy you are. For an athlete whose one-standard-deviation spread is about 23%, the old ±5% Balanced band was under a quarter of a standard deviation wide: in one 30-day sample only 5 days landed in it and 13 in the two outermost bands. Ordinary variation was being reported as signal, and a textbook recovery rebound the morning after a hard day came back as “Unusual”. Personal bands put Balanced where your normal days actually fall, and the labels leave the cause to you, because a single number cannot tell sleep debt from alcohol, illness, travel or a hard block. Each state’s guidance points you at resting heart rate, recent training and how you feel.
How to try it
On the web, open Home and find Normalized HRV in Today’s Metrics, or open Wellness and look at the key metrics cards. Click the card to open Where Today Sits and How It’s Classified.
On iOS, open Wellness and tap the Normalized HRV card to open the same detail sheet.
With Tempo connected to Claude or ChatGPT, try: “Where does my HRV sit this morning relative to my usual range, and how has the week trended?”
Note: The state badge and the personalized sections of the detail view require a Premium subscription; the percentage and calibration progress are visible to everyone. Normalized HRV needs both a resting heart rate and an HRV reading from the same night, so a scale that reports only resting heart rate does not contribute. Full method: Normalized HRV in the metrics glossary, and the write-up on the blog: https://jointempo.ai/blog/normalized-hrv-personal-states
Examples
