Lief initiates vibration feedback when your body dips below your target HRV range, similar to how a continuous glucose monitor device alerts a diabetic to low blood sugar. When you’re in this low HRV state, Lief automatically begins an HRV biofeedback dose (a.k.a. a Downtime Dose). As you breathe with Lief’s vibrations, your Lief monitors your HRV biomarker rise, then automatically ends the autodose when your HRV is back above the target range. As a result of this simple, continuous feedback loop, your body spends less and less time in the low HRV zone, and your average HRV increases over time, enabling your nervous system to respond more calmly in all situations.