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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

five pillars, resolved into one number.

01
collect
five pillars, each fed by signals from apple health and the meals you log in seconds.
02
normalize
each pillar is scored 0–100 against your own recent baseline — not a population chart — so they're comparable to each other and to your own last month.
03
weight
recovery 30%, nutrition 20%, activity 20%, stress 20%, habits 10%. published below, fixed, and identical to the ones in the app.
04
resolve
combined into one number from 0 to 100, recomputed every morning. yesterday's number is never rewritten.
the principle

freeze the facts, derive the opinion.

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 pillars

each pillar is scored 0–100 against your own recent baseline, then combined at a fixed share. the shares never move, and they never renormalize — a pillar with no data for the day contributes a neutral 50 rather than quietly handing its weight to the others.

recoveryshare of the score: 30%hrv, resting heart rate, respiration, and the architecture of last night's sleep. the largest share, because it is the signal that most changes what today should look like.
nutritionshare of the score: 20%macros, energy, and timing from the meals you log in seconds.
activityshare of the score: 20%training load weighted by heart-rate response, not minutes on feet.
stressshare of the score: 20%how well your autonomic signals settle, read against your own baseline. hrv leads; resting heart rate and respiration are weighted lower so the same autonomic signal isn't counted three times.
habitsshare of the score: 10%the streaks that compound: water, steps, consistency.

sleep is not a sixth pillar. it is the largest single input to recovery — which is why recovery carries the largest share.

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 variability
    Task 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 load
    Morton, Fitz-Clarke & Banister (1990). Modeling human performance in running. Journal of Applied Physiology 69(3):1171–1177.
    view source ↗
  • energy & metabolism
    Mifflin, 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 quality
    Monteiro, 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 architecture
    Carskadon, M. A. & Dement, W. C. (2011). Normal Human Sleep: An Overview. In Principles and Practice of Sleep Medicine, 5th ed., Elsevier, 16–26.
    view source ↗

sate informs. it doesn't diagnose. it is not a medical device, and nothing here is medical advice.

one honest number, every morning.

sate reads what your iphone and apple watch already collect, and what you log in seconds, and answers with a single score you can act on.

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