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Resopace
Slow paced breathing (5 breaths/min) — training for heart-rate variability (HRV).
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Requires a Polar H10 or any BLE heart-rate strap.
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10–20 min is typical. HRV stabilises after ~5 min.
min
Default 5 breaths/min. Premium can find their personal resonance frequency.
5.0 bpm
Pair a monitor above to enable Start.
Time to refresh your resonance
Your last calibration is over 90 days old. Resonance frequency can drift with fitness, sleep, and stress — a quick re-test keeps the pacer accurate.
~8 minutes · same protocol as before.
Use Chrome, Edge, Brave, or Android Chrome — Web Bluetooth isn't available in Safari or Firefox.
HR—bpm
Time left—
Beat-to-beat change—ms
HRV (last 60s)—ms
Get ready
Heart rate— – — bpm · last 2 min
Trial1 / 5
Rate—bpm
Trial time—
HR—bpm
Finding your resonance frequency…
Get ready
Your resonance frequency
—breaths / min
Strongest heart-rate response at this rate.
The best score was at the edge of the tested range — your true
resonance frequency may be slightly outside it. You can still use this
rate, but a re-test on another day may shift it.
Score per rate (taller = stronger heart-rate response)
Session complete
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See your full HRV scorecard
Track how your nervous system responds breath by breath — per-breath heart-rate range, overall HRV (SDNN, RMSSD), and coherence — on every session you've ever recorded.
€9.99 / month · cancel anytime.
HR trace
History
Session
HR trace
Heart-rate range per breath (RSA amplitude · taller = stronger breath/heart coupling)