Google is rolling out blood pressure trends, insulin resistance trends, and sleep breathing quality tracking to its Health Guardian suite on Pixel Watch 3, 4, and 5. These features analyze long-term physiological patterns using AI trained on sensor data rather than providing clinical diagnoses. The tools are free for Pixel Watch owners and available via Google Health Premium for Fitbit Air users.
Apple's new Readiness score and increased heart rate variability measurements on Apple Watch aim to assess autonomic nervous system health and predict disease, but claims about HRV's connection to health outcomes lack scientific proof. Consumer wearables measure HRV differently than clinical ECG methods, using optical pulse sensors rather than direct heart measurements, making direct comparisons problematic.