Lief’s patented “HRV autodose” feature makes HRV biofeedback responsive to your body, giving you just the right amount of biofeedback training to move your HRV biomarkers into a healthy zone, and gradually training your average HRV higher.

It works like this: Lief communicates with you through patented vibration patterns when your body dips below your target HRV range, similar to how a continuous glucose monitor device might alert a diabetic to low blood sugar. When you’re in this low HRV state, Lief automatically begins an HRV biofeedback dose.

As you breathe with Lief’s vibrations to sync your heart rate with your breath, Lief monitors your HRV biomarker rise, then automatically ends the dose 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.

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