What is Heart Rate Variability?
Heart Rate Variability (HRV) is the variation in the time interval between successive heartbeats. Contrary to intuition, a healthy heart does not beat like a metronome — it constantly adjusts its rhythm in response to breathing, stress, and environmental demands.
What It Measures
- •Parasympathetic tone — higher HRV generally indicates stronger vagal influence
- •Stress resilience — ability to recover quickly after challenge
- •Nervous system flexibility — capacity to shift between activation and recovery
- •Recovery capacity — readiness for physical and mental load
In ONDA Life
Increased HRV is a biological marker of Part 1 ("I Am") and Part 2 ("I Move") progress. Part 1 practices aim to support the parasympathetic system; effects on baseline HRV are modest and not guaranteed. Part 2 "Rhythmic Coherence" synchronizes axial movements with the respiratory cycle, which can raise HRV during the practice itself.
Read the science → Heart rate variability on ONDA Science — what HRV is, what it reflects and what it doesn't, with sources. The metrics in depth: RMSSD and SDNN; wearable accuracy: can you trust HRV from a smartwatch or ring?
References
- •Thayer & Lane, Neurosci Biobehav Rev (2009) — HRV as vagal tone marker
- •Lehrer et al., Appl Psychophysiol Biofeedback (2000) — resonance breathing and HRV