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Reference

Protocol Glossary

Science-backed definitions for every term in your health data: plain English and the mechanism behind it.

Biometrics

ALT & AST (Liver Enzymes)

Your liver's distress signal in a blood draw

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Biometrics

Autonomic Nervous System (ANS)

The body’s automatic regulatory control system

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Biometrics

Baroreflex Sensitivity (BRS)

How quickly your body corrects blood pressure swings

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Biometrics

Continuous Glucose Monitoring (CGM)

Real-time blood sugar dynamics on demand

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Biometrics

Cortisol Awakening Response (CAR)

The first hormonal signal that sets your day

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Biometrics

CRP (C-Reactive Protein)

Your body's systemic inflammation signal

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Biometrics

Fasting Glucose

Your baseline blood sugar after an overnight fast

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Biometrics

Ferritin

Your iron storage tank, and an inflammation marker

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Biometrics

GGT (Gamma-Glutamyl Transferase)

The liver enzyme most sensitive to alcohol and metabolic stress

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Biometrics

Glucose Variability

How much your blood sugar swings across the day

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Biometrics

Heart Rate Reserve (HRR)

The usable range between rest and maximum effort

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Biometrics

Heart Rate Variability (HRV)

Your nervous system's daily readiness signal

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Biometrics

Hemoglobin A1c (HbA1c)

A 3-month average of your blood sugar control

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Biometrics

HOMA-IR (Homeostatic Model Assessment of Insulin Resistance)

The earliest measurable signal of insulin dysfunction

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Biometrics

Iron Panel & Ferritin

Your iron storage and delivery system, measured in full

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Biometrics

LF/HF Ratio

A window into your autonomic nervous system balance

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Biometrics

Max Heart Rate (MHR)

The ceiling of your cardiovascular output

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Biometrics

Omega-3 Index (EPA + DHA)

Your cell membrane fatty acid quality score

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Biometrics

Orthostatic Heart Rate Test

A 60-second morning recovery readiness check

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Biometrics

Readiness Score

Oura's daily verdict on your capacity for stress

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Biometrics

Recovery Score

Your body's readiness verdict after last night

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Biometrics

Respiratory Rate

Breaths per minute: your body's quiet early warning signal

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Biometrics

Resting Heart Rate (RHR)

How hard your heart works when it doesn't have to

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Biometrics

RMSSD (Root Mean Square of Successive Differences)

The beat-to-beat calculation that powers your HRV score

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Biometrics

SDNN (Standard Deviation of NN Intervals)

The HRV metric Apple Watch uses, and why it reads higher than Oura

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Biometrics

Skin Temperature Deviation

Your body's overnight thermostat as a recovery signal

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Biometrics

SpO2 (Blood Oxygen Saturation)

The percentage of your red blood cells carrying oxygen

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Biometrics

Strain Score

Your daily cardiovascular load, accumulated

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Biometrics

Sympathetic vs. Parasympathetic

The two-branch system behind every readiness metric

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Biometrics

Uric Acid

A metabolic waste product that predicts more than gout

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Biometrics

Vagal Tone

The strength of your parasympathetic recovery signal

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Biometrics

VO2 Max

The strongest single predictor of long-term health and longevity

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More terms added regularly. Check back for new entries across all categories.

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