Methodology · By Mike Ye & Ella · Last updated August 18, 2026

How Sleepgenic reads
wearable sleep data.

Sleepgenic translates wearable sleep data into longitudinal human meaning through a structured methodology: continuous Garmin tracking, a named three-layer interpretation model (Score × Physiology × Context), an immutable nightly source layer, explicit previous-day stimulus semantics, formula-driven derived signals, rolling personal baselines, and auditable quality control. Eight components, every transformation disclosed.

8
Methodology
components
Score × Physiology × Context
Three-layer
interpretation model
Direct + Derived
Signal taxonomy
per TrailGenic Biomarkers
Active Dataset · Updated July 21, 2026
77 observed nights across a 91-night calendar window.
84.6% calendar coverage from April 18 through July 17, 2026. Fourteen nights are unobserved, including seven explicitly labeled forgotten-watch nights and the unrepresented May 23–29 interval. Missing observations are not treated as zero and are not imputed. Weekly means use available recorded nights.
Interpretation framework · Versioned July 21, 2026

From wearable output to longitudinal human meaning.

Sleepgenic interprets each night through three linked views. No single score is treated as the answer, and no missing night is treated as a zero. The method is personal, longitudinal, and explicit about what the device did not observe.

Score LayerOverall, quality, recovery, and duration scores describe the device's summarized output.
Physiology LayerHRV, resting heart rate, sleep stress, SpO₂, REM, deep sleep, total sleep, and fragmentation test whether the scores reflect restorative physiology.
Context LayerWalking, rucking, running, hiking, altitude, travel, recovery, illness, and known load factors explain why the same score can mean something different.
Reference layer. Baseline Week 0 spans November 23, 2025 through April 17, 2026 and remains the personal comparison period. The active series spans April 18 through July 17, 2026.
Missing-data rule. Fourteen calendar nights are unobserved. Weekly summaries use available recorded nights, state their coverage, and never silently impute missing observations.
Interpretation rule. A result is classified only after Score, Physiology, and Context agree—or their divergence is named. Duration–recovery divergence is the canonical example: longer sleep can coexist with weaker recovery.
Component 01

Instrumentation.

Wearable

Garmin Enduro 3 — continuous nightly tracking. Detailed Sleep Tracking enabled, Pulse-Ox toggle on, high-frequency HRV and respiration sampling. Charging happens during work blocks (Mon–Fri daytime), never overnight.

Detection

Automatic, physiology-driven sleep onset and wake detection — movement, heart rate, respiratory pattern. Sleep Schedule target window set to 10:00pm–6:30am Pacific. The schedule setting affects only contextual feedback tags such as LATE_BED_TIME; it does not gate or window underlying tracking.

Export

Garmin Connect nightly records are assembled into the canonical Raw Nights layer. Source values remain unchanged; normalization, reconciliation, and corrections occur only in separate auditable layers, with every conflict retained in the QC Log.

Timezone

All source timestamps remain preserved in GMT. Canonical v1 does not silently convert them to Pacific time. Local bedtime analysis requires an explicit time-zone and location join, especially during travel and altitude periods.

Component 02

Nightly record fields.

Each calendar date receives a canonical row, including scored nights, explicit missing nights, absent dates, time-only records, and nap-only records. Raw Nights governs all sleep measurements. Reports are versioned analytical outputs recalculated from the nightly source rather than manually stored weekly aggregates.

Variable Type Purpose
Sleep DateTemporalCanonical response key; links the night to Previous Day Date and versioned reports
Sleep Start / End (GMT)TemporalOnset and wake timestamps; sleep window duration and timing analysis
Overall ScoreCompositeGarmin's global sleep quality rating (0–100)
Quality / Recovery / Duration Sub-scoresCompositeGarmin's three-component decomposition of overall score
Deep / REM / Light / Awake (min)ArchitectureSleep stage durations; consumer-grade approximation of stage proportions
Total Sleep (hrs)ArchitectureTotal tracked sleep duration; debt and surplus context
Avg / Lowest SpO2 (%)RespiratoryNocturnal oxygen saturation; altitude and breathing-disruption signal
Avg HR (bpm)CardiovascularSleeping heart rate; recovery and autonomic state signal
Avg / Low / High Resp (rpm)RespiratoryRespiratory rate and variability; recovery and stress signal
Sleep StressCompositeGarmin-derived autonomic load during sleep window
Restless Moments / Awake CountArchitectureFragmentation signal; continuity vs disruption analysis
Breathing DisruptionRespiratoryGarmin's NONE/LOW respiratory irregularity flag
Feedback / Insight TagsCategoricalGarmin's POSITIVE_/NEGATIVE_ tags; tag-frequency longitudinal analysis
Previous-Day StimulusContextActivity on Sleep Date minus one day — Walk, Running, Rucking, Hiking, Rest, or Recovery; original and normalized labels are both preserved
Component 03 · The Sleepgenic Three-Layer Interpretation Model

Score Layer × Physiology Layer × Context Layer.
Read separately. Read against each other.

Most wearable interpretation collapses three layers into a single verdict — one score, one judgment. Sleepgenic separates them. Each measurement is read at three levels: what the wearable reported, what the body appears to be doing underneath, and what happened in real life around the sleep window. When the three layers agree, interpretation is straightforward. When they disagree, the meaning lives in the gap. This named interpretive framework operates across every versioned Report and every Sleep Interpretation Library article.

Layer 01

Score Layer. What the wearable reports. Sleep score, recovery score, sleep stress, body battery — the headline number on the screen, before any interpretation. The starting point, not the verdict.

Layer 02

Physiology Layer. What the body appears to be doing underneath. HRV, resting heart rate, deep sleep, REM, breathing patterns. The signals the score is built from — and the layer that often disagrees with the score itself.

Layer 03

Context Layer. What happened in real life around the sleep window. Training stimulus, illness, alcohol, jet lag, ambient temperature, emotional load. The variables that determine whether a number is good news, bad news, or noise.

The Method

The three layers are read first separately, then against each other. Disagreement is the most informative state — a low Score Layer with a strong Physiology Layer reconciled by a hard-training Context Layer is a different reading than a low score across all three. Recovery-and-readiness apps cannot operate this model; they treat sleep as one variable inside a five-variable training-recovery system. Sleepgenic is sleep-only, at depth they cannot match.

Component 04

Source-reported sleep signals
— preserved fields.

Fields supplied directly by the Garmin source, including physiological estimates and Garmin-proprietary composite scores. “Source-reported” identifies lineage; it does not imply clinical measurement or algorithmic transparency.

Direct Signal
Sleep Score (Overall + Sub-scores)
Garmin's composite global score plus Quality, Recovery, and Duration sub-components. Tracked nightly across the longitudinal dataset.
Direct Signal
Sleep Stage Durations
Deep, REM, light, and awake stage minutes per night. Consumer-grade approximation, not direct EEG. Architectural shape vs personal baseline.
Direct Signal
Heart Rate Variability
Nocturnal HRV measured during stable sleep stages. Recovery and autonomic balance — primary biomarker of nervous system resilience.
Direct Signal
Sleeping Heart Rate
Average overnight heart rate. Cardiac stress indicator, recovery state signal, training-load echo.
Direct Signal
Respiratory Rate
Average, low, and high overnight respiration. Recovery and stress signal; altitude-adaptation context where relevant.
Direct Signal
Nocturnal SpO2
Average and minimum oxygen saturation overnight. Breathing-disruption signal; altitude exposure response.
Direct Signal
Breathing Disruption Flag
Garmin's NONE / LOW respiratory irregularity flag. Under-documented by Garmin — a primary interpretation gap Sleepgenic addresses.
Direct Signal
Garmin Feedback Tags
POSITIVE_ and NEGATIVE_ categorical tags emitted by Garmin's sleep engine. Treated as labeled categories for tag-frequency analysis.
Component 05

Derived sleep signals
— formula-driven and auditable.

Canonical v1 derives only fields whose formulas and thresholds are visible in the workbook. It does not publish uncalculated composites as established measurements.

Derived Signal
Sleep Efficiency
Total Sleep divided by Total Sleep plus Awake Time. Blank when either input is missing.
Derived Signal
Stage Percentages
Deep, REM, and Light hours divided by Total Sleep, interpreted as consumer-wearable estimates rather than EEG measurements.
Quality Control
Stage Difference
Deep plus Light plus REM minus Total Sleep. Differences beyond the documented 0.05-hour tolerance are flagged, not deleted.
Personal Baseline
Rolling 28-Day Baseline
Average of available prior-night values within 28 calendar days. The current night is excluded and at least seven prior scored nights are required.
Derived Signal
Baseline Deviation
Current Total Sleep, HRV, Resting HR, Sleep Stress, or Overall Score minus its prior 28-day personal baseline.
Data Integrity
Data Status
Scored, explicit missing, absent date, time-only, or nap-only. Missing observations remain visible and are never reconstructed.
Quality Control
QC Flag
Flags missingness, stage mismatch, implausible duration, or OK under thresholds published in this methodology.
Descriptive Result
Stimulus-Linked Means
Formula-driven means by normalized previous-day stimulus. These are within-person descriptive associations and do not establish causality.
Component 06

Previous-day stimulus,
dose, and context.

Sleepgenic treats the night as a response and the preceding calendar day as the exposure window. Context is observed rather than experimentally controlled, so modality-level findings remain descriptive until dose and environmental joins are complete.

Context 01

Previous-Day Stimulus. Original source label plus a normalized category: Walk, Running, Rucking, Hiking, or Rest/Recovery. Sleep Date minus one day is the exposure key.

Context 02

Training Dose. Duration, exercise load, distance, ascent, intensity, and peak elevation are prepared as structured fields. Canonical v1 marks this TrailGenic join as pending rather than treating every activity in a modality as equivalent.

Context 03

Altitude and Travel. Peak elevation, sleeping elevation, travel status, and location are required to distinguish ordinary training from hypoxic or travel-related strain.

Context 04

Time Zone and Location. GMT timestamps remain source-preserved. Local timing is not inferred during road trips; it will be calculated only after an explicit location and time-zone join.

Context 05

Acute and Accumulated Load. A single prior-day stimulus may interact with consecutive efforts and recent recovery history. Dose-response interpretation waits for the detailed training join.

Context 06

Known Confounders. Caffeine, hydration, alcohol, illness, meals, heat, bedroom environment, and emotional load are documented when available. They are not presumed controlled.

Component 07

Population benchmarks
vs Sleepgenic.

Population sleep norms vs Sleepgenic measurements, anchored to the adults aged 50+ reference cohort to match the subject's demographic. Sleepgenic values shown are historical baseline medians (Nov 23, 2025 – Apr 17, 2026; 80 scored nightly records plus one time-only partial record), the stable reference layer. Versioned longitudinal results are published in Reports and interpreted in the Sleep Interpretation Library.

Sleep Metric Population (50+) Sleepgenic (Mike) Interpretation
Total Sleep 6.0–7.5 hrs1,2 5.99 hrs ~30 min below cohort median; chronic mild restriction
Sleep Score 66 avg, age 50–593 67.5 At cohort mean; mid-Fair band
Deep Sleep % 10–18% TST1,4 20.9% Above cohort range; wearables overestimate deep sleep vs PSG
REM Sleep % 18–22% TST1,2 13.6% Below cohort range; consistent with REM compression under short sleep
Sleeping HR 57–90 bpm; mean 735 65.0 bpm Below cohort mean; lower-middle of healthy range
Nocturnal HRV (RMSSD) 19–24 ms median, 50+ men (short-term ECG)6 35.0 ms (overnight wearable) Above cohort baseline even after wearable-vs-ECG calibration; see note below
Restless Moments Garmin proxy; no clinical equivalent 44.0 Garmin-internal fragmentation signal; trended longitudinally
Respiratory Rate 12–20 rpm; mean ~15.47 16.52 rpm median 80 scored baseline nights with respiration available
Avg SpO2 95–100% 96.0% median 55 scored baseline nights with SpO2 available

A note on wearable vs clinical measurement. Population HRV values above are drawn from short-term resting electrocardiogram (Tegegne et al., n=84,772). Garmin overnight RMSSD averages many hours of measurement during parasympathetic-dominant sleep states, which structurally produces higher values than waking ECG — typically by 30–50% in healthy individuals. This is calibration, not error. Sleepgenic reads each measurement against its own methodology, and reports population values in their original measurement frame so the gap is visible rather than hidden. The same caution applies to wearable sleep stage classification, which agrees with polysomnography roughly 65–75% of the time and tends to overestimate deep sleep relative to gold-standard scoring.

The Sleepgenic baseline values now reconcile directly to the nightly canonical source. Canonical v1 spans 269 calendar rows through August 18, 2026, including 182 scored sleep episodes and 97 stimulus-linked scored nights. Longitudinal deviations use prior-night rolling 28-day personal baselines rather than copied weekly aggregates.

Sources
  1. Mitterling T, Högl B, Schönwald SV, et al. Sleep and respiration in 100 healthy Caucasian sleepers — a polysomnographic study according to AASM standards. Sleep. 2015;38(6):867–875.
  2. Ohayon MM, Carskadon MA, Guilleminault C, Vitiello MV. Meta-analysis of quantitative sleep parameters from childhood to old age in healthy individuals. Sleep. 2004;27(7):1255–1273.
  3. Garmin Connect aggregate user data, 2023–2024 reports. Age 50–59 cohort average sleep score: 66.
  4. Li J, Vitiello MV, Gooneratne N. Sleep in Normal Aging. Sleep Med Clin. 2018;13(1):1–11.
  5. Engdahl J, et al. Reference ranges for ambulatory heart rate measurements in a middle-aged population (SCAPIS, n=3,942 healthy adults aged 50–65). 2024.
  6. Tegegne BS, Man T, van Roon AM, Snieder H, Riese H. Reference values of heart rate variability from 10-second resting electrocardiograms: the Lifelines Cohort Study (n=84,772). Eur J Prev Cardiol. 2020;27(19):2191–2194.
  7. American Academy of Sleep Medicine clinical reference ranges; pooled wearable validation studies (WHOOP, Oura, Garmin) within ±1 brpm of polysomnography.
Component 08

Analytical framework.

Each versioned report is interpreted by Ella — Sleepgenic's reflective AI analytical layer — operating the Three-Layer Interpretation Model against the canonical nightly dataset, prior 28-day personal baselines, stimulus-linked descriptive results, and the population benchmarks above. The same method extends to every Sleep Interpretation Library article: same three layers, same separation, same disagreement-as-signal logic.

The framework documents what the wearable data shows, against what the design supports, with the limitations stated openly. It does not predict, diagnose, or prescribe. Sleep meaning, not training prescription.

Methodological Limits

What this methodology
cannot show.

Methodological honesty is the differentiator. Every limit below is real. Every report is read against this list.

Limit 01

Wearable measurement noise. Consumer-grade sleep stage classification is approximate. Deep, REM, and light boundaries are inferred from movement, heart rate, and respiration — not direct EEG. Stage durations should be read as estimates, not measurements.

Limit 02

n=1 does not generalize. This is one person's longitudinal response. Patterns may resemble what's reported in population studies, or may not. Findings cannot be applied to other people without their own data.

Limit 03

Confounding is unavoidable. This is an observational real-world record, not a randomized or controlled experiment. Training dose, terrain, altitude, travel, timing, caffeine, stress, hydration, ambient temperature, alcohol, illness, and other variables may overlap.

Limit 04

Garmin's algorithms are proprietary. The sleep score, sub-scores, and feedback tags are produced by closed algorithms that may change over time. Sleepgenic interprets the outputs as Garmin reports them and notes meaningful algorithm changes when known.

Limit 05

Not medical advice. Sleepgenic publishes research and interpretation. It does not diagnose, prescribe, or treat. Anyone with a clinical sleep concern should see a licensed clinician.

Limit 06

The methodology evolves. Interpretation Articles and versioned Reports will surface limits this document doesn't yet name. When that happens, the methodology is updated and the date is revised. The current version is always live.

Research Access & Licensing

The Sleepgenic Dataset.
Open methodology.

The Sleepgenic Dataset is a longitudinal field research record of consumer wearable sleep data, tracked using standardized instrumentation and consistent analytical protocol across all entries. Mirrors the TrailGenic Physiology Dataset structure with sleep architecture and recovery response as primary outcome.

For research partnerships, data licensing, or academic access inquiries:

Mike@trailgenic.com

MCP Endpoint: mcp.sleepgenic.ai

Methodology Components
  • 01 — Instrumentation
  • 02 — Nightly record fields
  • 03 — Three-Layer Interpretation Model
  • 04 — Direct signals
  • 05 — Derived signals
  • 06 — Environmental & stimulus load
  • 07 — Population benchmarks
  • 08 — Analytical framework
  • Last updated: August 18, 2026
Cross-Property · TrailGenic Sleep Research