HRV4Training

HRV4Training is the first scientifically validated HRV app, delivering HRV-based insights to quantify stress, balance training, and improve performance. It measures HRV using your phone’s camera (no chest strap required) and also works with Apple Watch, Oura Ring, and Bluetooth SMART sensors. The app tracks day-to-day HRV changes in response to stressors and long-term multi-parameter trends to reveal the bigger picture. It correlates physiological measurements with user annotations and provides training-load analysis, readiness to perform, and injury-risk indicators. VO2max estimation for runners, linked to Strava or TrainingPeaks, is supported along with Training Polarization (80/20) and lactate-threshold estimation, plus weekly and monthly progress summaries. All data is processed in-app for privacy and quick, actionable interpretation, with options to export or back up.

Additional features include TAGS for sleep, energy, muscle fatigue, stress, and other factors that influence physiological stress; data export via email or Dropbox; Health app integration; a configurable test (1, 3, or 5 minutes); live PPG signal view for signal quality; population summaries and comparisons; and recovery points. HRV4Training requires an account to back up data and does not provide medical advice; it is intended for informational purposes only. For deeper understanding, see the linked literature in the guide.