The Science
Baku's analytics are grounded in peer-reviewed research across sleep science, cardiovascular physiology, and longevity medicine.
Core Biomarkers
Baku focuses on a small set of biomarkers with strong evidence linking them to health outcomes. We chose depth over breadth.
HRV is the variation in time between successive heartbeats, controlled by the autonomic nervous system. Higher HRV generally indicates greater parasympathetic tone — a sign the body is well-recovered and adaptable. Baku uses overnight HRV as its primary recovery signal, interpreted against your personal baseline.
Sleep cycles through distinct stages — light NREM, deep slow-wave sleep, and REM — each serving different biological functions. Deep sleep drives physical restoration. REM sleep drives cognitive restoration. Baku tracks the proportion and timing of each stage against your personal norms.
VO2 max is one of the strongest predictors of long-term health and longevity in the research literature. Baku estimates VO2 max from your wearable data and tracks it over time as a core longevity marker.
Day-to-day elevations in RHR relative to your personal baseline are a sensitive early signal of illness, overtraining, or poor recovery — often appearing before subjective symptoms.
Our Methodology
We collect 2–4 weeks of data before making strong interpretive claims. Your baseline is a rolling window of your own history — not a fixed population average.
Each data point is compared to your baseline distribution. Statistically significant deviations are flagged and weighted in your daily scores.
No single biomarker tells the full story. Baku integrates signals across HRV, RHR, sleep architecture, and activity load to produce composite scores.
Baku converts every insight into a clear, evidence-based recommendation — explaining the reasoning behind every suggestion.
On Personalization
An HRV of 45ms might be excellent for one person and below average for another. Population averages obscure these individual differences. Baku is built around the principle that your data should only ever be compared to your own history.
A Note on Wearable Data
Consumer wearables are not medical devices. Baku treats wearable data as a high-frequency signal most valuable for tracking relative changes over time. We do not claim clinical-grade accuracy. We do claim that the trends Baku surfaces are meaningful — and that acting on them thoughtfully will improve your health.