Evidence: Apple Watch heart health features: continuous resting HR, HRV, cardio fitness (VO2 max estimation), Low/High HR notifications, irregular rhythm notification, FDA-cleared ECG app. VO2 max validated by Apple research study (JMIR 2021). ↗
Evidence: Fitbit PurePulse 2.0 HR sensor: continuous all-day HR, resting HR trend, HR Zones for exercise, high/low HR notifications, irregular rhythm notifications (Charge 5+/Sense 2/Pixel Watch). Irregular rhythm notification received FDA 510(k) clearance for AFib screening (Fitbit Sense/Charge 5, cleared December 2022). ↗
Evidence: Garmin Elevate HR sensor: continuous 24/7 HR tracking, resting HR trend, HRV Status (long-term HRV baseline + acute deviation), abnormal HR alerts. Health Snapshot (60-second HRV, SpO2, respiration, pulse ox, stress). No ECG on current consumer models (ECG was on Garmin Venu 3; discontinued on some). ↗
Evidence: Oura Ring heart rate monitoring explainer: PPG sensor measures resting heart rate, heart rate variability (HRV), average heart rate during the day and during sleep. Oura claims +/-2 bpm accuracy vs. ECG reference. ↗
Evidence: RingConn Gen 2 tracks 24/7 heart rate and HRV. Features high and low HR alerts. No ECG capability; optical PPG only. No FDA clearance for heart health monitoring. ↗
Evidence: Ultrahuman Ring Air tracks resting heart rate, HRV (RMSSD), and heart rate during activities. Outputs Movement Score and Recovery Score. Uses HRV as primary readiness input. No FDA clearance; wellness device only. ↗
Evidence: WHOOP MG (Medical Grade) product page: adds medical-grade ECG, non-invasive blood pressure monitoring (without a cuff), and continuous blood glucose monitoring via NovaBay Pharmaceuticals partnership. WHOOP MG requires $399/yr subscription vs. standard $199-$359. Blood pressure feature is maker-claimed; independent clinical validation not yet published. ↗