What Is HRV
Short answer
HRV is a measure of variation between heart beats. In practice, it is most useful as a trend signal for recovery and stress, not as a daily command.
What is HRV
Heart rate variability describes how much time varies between beats. Higher is not always better in every moment, but stable context-aware trends are useful.
Why it matters
When HRV shifts together with poor sleep, rising resting heart rate, or heavy training, it can help confirm that your system is under more strain.
Factors
Sleep loss, illness, stress, alcohol, travel, and hard training can all affect HRV. Device quality and measurement timing matter too.
How to use it
Measure under consistent conditions and compare against your own baseline. Weekly direction is more useful than isolated spikes.
Mistakes
Do not cancel training because of one low reading if everything else feels normal. Context matters more than a single metric.
FAQ
If your HRV is lower than someone else's, that tells you almost nothing. Your baseline matters more than comparison with other people.
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