Stress, as it happens.

What the score means

• Calm 0–25
• Mild 26–50
• Elevated 51–75
• High 76–100

Sitting calm and awake reads about 20; deep sleep reads about 2. A heart rate 8 beats a minute above your calm with 30 % less variability reads 60, Elevated. 20 beats above with half the variability reads 93, High.

Stress says what your heart is doing, not why. Anything that raises your heart rate or lowers your HRV while you sit still reads the same way: a tense meeting, caffeine, a warm room, a big meal, alcohol or illness.

Only while you’re still

Movement raises your heart rate for reasons that aren’t stress, so Keely doesn’t score it. A 5-minute window shows as Active, never as stress, when:

• any minute in it has more than 10 steps, or the Loop rates it as more than light activity;
• it overlaps a workout;
• your heart rate is at or above your Zone 1 floor, which catches rides and lifting that barely move the wrist.

After activity, windows stay unscored while your heart rate settles, as long as it’s more than 15 beats a minute above resting: for up to 30 minutes after a workout, and up to 10 minutes after a walk.

How the score is computed

Both signals are compared with a calm and awake reference taken from your nightly baselines: your resting heart rate plus 12 beats a minute, and about 78 % of your nightly HRV.

zHR    = (HR − (resting HR + 12)) ÷ 8
zRMSSD = (ln RMSSD − (ln nightly HRV − 0.25)) ÷ 0.35
s      = 0.9 × zHR − 0.9 × zRMSSD
Stress = 100 ÷ (1 + e^−(s − 1.4))

Without enough clean beats for RMSSD, heart rate carries the reading alone: s = 1.2 × zHR.

Until you have 3 nights, Keely uses your profile’s resting heart rate (or 60) and an HRV of 45 ms, and treats the reading as provisional.

Live and stored

• Live. With your Loop connected and Keely open, heart rate and beat intervals stream from the band, and the score covers the last five minutes once they hold two minutes of heart rate. The stillness rule still applies: a minute where the Loop flags at least half its beats for movement or lost contact counts as moving.
• Stored. The rest of the time, Keely scores the Loop’s 24/7 data when it syncs, and labels the reading with its time, such as “As of 11:20”. Gaps stay gaps.

Moments

A moment is when stress stood out: at least two windows in a row (10 minutes) above 50 during the day, or above 30 at night. Moments show on the timeline, day and night.

Frequently asked questions

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