What are R-R intervals?
Heart rate variability (HRV) is NOT heart rate. Heart rate is just your average number of heartbeats, while HRV is the tiny difference BETWEEN each heartbeat.
HRV is a powerful biomarker that has helped millions to:
- Improve training and recovery
- Get fitter, faster, and stronger
- Get healthier and address chronic disease
- Manage stress
- And much more!
Key to the power of HRV is its deep connection to your nervous system, which controls and responds to many important body processes, like:
- Digestion
- Respiration
- Metabolism
- Vision, hearing, and smell
- Sexual function
- and more
This connection requires tracking small changes (milliseconds) in the intervals between successive heartbeats (Fig 1 above), also called "R-R intervals". This is different from heart rate, which just averages the number of beats per minute.