Heart rate variability (HRV)
Heart rate variability, usually shortened to HRV, measures the small differences in timing between one heartbeat and the next. A higher HRV is generally associated with a body that is well rested and coping well with current demands; a lower HRV, relative to a person's own normal range, often signals accumulated stress or incomplete recovery.
HRV is highly individual. What counts as a high or low reading varies enormously between people, which is why it is far more useful compared against someone's own recent average than against a population norm or a round number.
Wearables such as Oura and Whoop measure HRV overnight and surface it as part of a readiness or recovery score. Sloane reads this data, where a person has connected a supported device and treats meaningful drops against a person's own baseline as one input among several, alongside calendar and team-tool signals.
HRV on its own does not explain why a change has happened. It is a physiological signal, not a diagnosis, and Sloane treats it as one piece of evidence to weigh against everything else it can see about a person's week, not as a standalone verdict.
Related terms
- Resting heart rate, The number of times the heart beats per minute at rest, typically measured overnight, where a rise above a person's normal range can indicate stress or incomplete recovery.
- Recovery score, A composite daily score, produced by a wearable, that summarises how well rested and prepared a person's body appears to be for demanding activity.
- Readiness, A daily estimate of how prepared a person is to take on demanding work, based on overnight physiological recovery relative to their own baseline.
- Personal baseline, The rolling normal range for a specific individual across their signals, used as the point of comparison for deciding whether something has genuinely changed.