PolarH10Windows-first telemetry toolkit
PolarH10 Developer Reference

Breathing Dynamics Workflow

Open the dynamics window after breathing calibration, wait through the readiness ramp, and use the dedicated feature view when the Live tab summary plots are too small.

The Dynamics window is the breathing-dynamics operator surface. It uses the calibrated breathing base waveform, detects alternating extrema, derives breath interval and amplitude series, and computes a feature bundle for each series.

Method Provenance

This window follows the breathing-dynamics feature family described by Goheen et al. in Psychophysiology (2025): breath interval and breath amplitude series, then mean, SD, CV, ACW50, PSD slope, LZC, sample entropy, and multiscale entropy for each derived series.

The implementation here is intentionally explicit about one adaptation: the paper derives those series from a respiration-belt signal after its own preprocessing, while this app derives them from the calibrated ACC breathing base waveform already exposed by the Polar breathing tracker.

The paper also cites NeuroKit2 for the entropy and complexity functions. Where the paper does not publish exact entropy hyperparameters, this app uses fixed defaults that stay close to that path:

  • SampEn: m=2, delay=1, r=0.2 * SD
  • MSE: m=3, delay=1, r=0.2 * SD, scales 1..5, summary=AUC

Use the window's Method references panel or the shared References page if you need the paper DOI, the linked paper-code repo, or the NeuroKit2 source pages.

The runtime now also suppresses undefined entropy solves instead of inventing a finite fallback value, so the app stays closer to the NeuroKit2 behavior cited by the paper when short or overly regular series fail the conditional-match step.

Open formula sheet Download Markdown Download PDF

What The Window Exposes

  • headline Interval entropy and Amplitude entropy tiles
  • tracker readiness, recording maturity, and entropy confidence state
  • counts for accepted extrema plus retained interval/amplitude breaths
  • feature bundles for mean, SD, CV, ACW50, PSD slope, LZC, sample entropy, and multiscale entropy
  • reset, apply-tuning, and restore-defaults controls aligned with the coherence window
  • a dedicated chart and log stream for the currently selected device

Parameter Meanings

  • Extremum delta: minimum waveform change required before a trend reversal is treated as a candidate peak or trough.
  • Peak/trough gap (s): minimum allowed time between alternating accepted extrema.
  • Peak-trough excursion: minimum waveform excursion required for a completed breath to count.
  • Retained series size: rolling history length kept for the derived interval and amplitude series.
  • Basic-stats warmup: minimum derived-breath count before mean, SD, CV, ACW50, and PSD slope are shown.
  • Entropy warmup: minimum derived-breath count before LZC, sample entropy, and multiscale entropy are shown.
  • Confidence target: longer-recording target used for Recording maturity and Entropy confidence.
  • Recording maturity: warmup score based on the smaller of the interval and amplitude series sizes, scaled from Basic-stats warmup to Confidence target.
  • Entropy confidence: confidence score that stays at zero until both interval and amplitude entropy are available, then ramps toward Confidence target.
  • SampEn m / delay / r·SD: sample-entropy embedding dimension, delay, and tolerance as a multiple of signal SD.
  • MSE m / delay / r·SD: multiscale-entropy embedding dimension, delay, and tolerance as a multiple of signal SD.
  • MSE max scale: largest coarse-graining scale used before the entropy-by-scale curve is reduced to AUC.

Manual App Test

  1. Wear the strap and wet the electrodes.
  2. Start the app and connect to the intended strap.
  3. Confirm HR and ACC counters are moving on the Live tab.
  4. Open Breathing and complete calibration until the tracker is live.
  5. Return to Live and open Dynamics window.
  6. Check the top status line:
    • before enough breaths accumulate, entropy should stay unavailable
    • readiness should move from collecting breaths to basic stats, then to entropy-ready
  7. Keep breathing normally while the warmup runs.
  8. Confirm the dynamics window starts updating:
    • interval entropy and amplitude entropy leave --
    • interval and amplitude breath counts increase
    • recording maturity and entropy confidence move upward over longer recordings
  9. Use the shared telemetry selector if you want the Live tab to plot:
    • Breath interval entropy
    • Breath amplitude entropy
  10. Adjust tuning only if needed:
    • Apply tuning resets the tracker with the new thresholds
    • Restore defaults returns to the app defaults
    • Reset tracker clears the current derived-history window

Fast Failure Checks

  • If the status line says calibration is required, the breathing tracker is not ready yet.
  • If the window stays in Waiting for breathing tracking, ACC is flowing but the calibrated waveform is not stable enough for cycle extraction.
  • If interval or amplitude counts stay near zero, the extrema thresholds are too strict for the current signal or the breathing waveform is too flat.
  • If shared telemetry plots stay flat at zero while the window is still warming up, that is expected until entropy becomes available.

Related Pages