Heart rate variability is the most misread number on a wearable. It is not a fitness score and not a wellness grade; it is a rough readout of autonomic balance, and it swings for reasons that have nothing to do with how virtuous your week was. Alcohol, a late meal, a hot room, an infection coming on, the luteal phase of a menstrual cycle and a hard session the day before will all move it.
That variance is why the absolute number is close to useless for comparison between people, and why your own rolling baseline is the only sensible reference. These posts cover what HRV measures, what a normal range looks like at different ages, why yours might be low, and which interventions have evidence behind them rather than testimonials.
Pedro Thomaz builds Vitra, a desktop app that reads Oura data against your own baseline instead of a population average. He has worn a ring daily for years and reads these same numbers every morning — which is where most of what is written here comes from. Vitra is not a medical device and nothing on this blog is medical advice.
Local AI on your Mac or PC. One-time purchase, 7-day trial, no Vitra subscription.
Download Vitra →