Heart Rate Variability (HRV) is a useful health metric, but most people measure it wrong. Marco Altini's guide explains the proper protocol.
The core issue: consistency matters. Apple Health collects HRV randomly throughout the day, making the data practically useless for tracking trends. You need measurements at the same time each day, away from stressful moments.
The Protocol
- Timing: Immediately after waking up, before getting out of bed
- Position: Sitting still
- Tool: Use the Apple Watch Mindfulness app (formerly Breath)
- The breath exercise manually triggers an HRV reading
- This creates a consistent, controlled measurement
The App Setup
Use Athlytic (not Apple Health) to analyze your data:
- Configure it to pull only manually triggered measurements
- This filters out the random daytime readings
- Switch calculation method to rMSSD instead of default SDNN
- Ensure it has read access to beat-by-beat measurements
Why This Matters
Chest straps like Polar H10 are the gold standard, but Apple Watch is surprisingly decent if used correctly. The key is creating a repeatable protocol that minimizes variables.
Most people who say "HRV tracking doesn't work for me" are actually just measuring inconsistently. Random measurements throughout the day capture stress, caffeine, meals, and a hundred other confounders rather than your baseline recovery.
Marco's full article on Apple Watch and HRV goes deeper into the technical details and validation studies.