the method
the science.
sate reads the signals your iphone and apple watch already collect, then resolves them into one number — recomputed every morning. here's how, and the science it stands on.
how the score is built
the principle
sate stores what your body did as it happened, and computes the reading fresh each time — so a better night never silently rewrites yesterday. the facts are frozen; the opinion is derived on read.
the five domains
sleepduration, debt, and the architecture of the night — deep, rem, light.
nutritionmacros, energy, and timing from the meals you log in seconds.
movementtraining load weighted by heart-rate response, not minutes on feet.
recoveryhrv, resting heart rate, respiration — your morning readiness.
habitsthe streaks that compound: water, steps, consistency.
the science behind the signals
sate doesn't run its own studies. it computes from your apple health data and established physiology. the published methods those signals rest on:
- heart-rate variabilityTask Force of the ESC & NASPE (1996). Heart rate variability: standards of measurement, physiological interpretation, and clinical use. Circulation 93(5):1043–1065.view source ↗
- training loadMorton, Fitz-Clarke & Banister (1990). Modeling human performance in running. Journal of Applied Physiology 69(3):1171–1177.view source ↗
- energy & metabolismMifflin, St Jeor, Hill, et al. (1990). A new predictive equation for resting energy expenditure in healthy individuals. American Journal of Clinical Nutrition 51(2):241–247.view source ↗
- food qualityMonteiro, Cannon, Levy, et al. (2019). Ultra-processed foods: what they are and how to identify them. Public Health Nutrition 22(5):936–941.view source ↗
- sleep architectureCarskadon & Dement (2017). Normal Human Sleep: An Overview. In Principles and Practice of Sleep Medicine, 6th ed., Elsevier, 15–24.
sate informs. it doesn't diagnose. it is not a medical device, and nothing here is medical advice.