Under Menu > Training, you can access different dose types for your Lief device. We describe the different dose types and their possible use cases below:
Downtime: Helps restore vagal tone through slow and deep breathing exercises that sync heart rate with respiration (a.k.a HRV biofeedback). Downtime begins either when you self-initiate it (by tapping your Lief once while it's on your body, or through the app), or when your HRV has dropped below the lower bound of your threshold settings (a.k.a. Auto-doses).
Here's how Downtime works: Your Lief starts vibrating when it senses that your heart rate is dropping. When your heart rate begins accelerating again, the algorithm turns the vibration off. When your Lief is vibrating, that’s your cue to begin exhaling because your heart rate is decelerating at that moment. The goal of the practice is to sync breath rhythm with heart rate such that when you’re exhaling, it syncs up with the deceleration of your heart rate, and when you’re inhaling it syncs up with the acceleration of your heart rate.
Downtime helps activate vagal pathways that counteract the flight-or-fight stress response. As a result, it lowers defenses, relaxes the body, slows heart rate, encourages feelings of centeredness and calm, and improves decision-making abilities.
Heartbeat: Enables you to listen to your real-time heartbeat through vibration feedback. You could use this mode to help you become more acquainted with the rhythm of your heart in different contexts, or ease into the sensation of feeling a vibration that indicates your heart's rhythm.
Paced breathing: The Lief vibrates to guide a 4 count inhale and a 6 count exhale. This mode helps you engage in slow, deep, diaphragmatic breathing at a predictable pace. While it's not an HRV biofeedback exercise because it's not responding to your heart rate in real-time like a Downtime session, it can have a calming effect, especially for those who want consistent, predictable pacing for each inhale and exhale.
Nudge (relevant for auto-dosing only): This mode can be used to passively notify you which HRV zone you're in. You'll receive vibrations to alert you which HRV zone you're in (1=red/lowest; 5=blue/highest), but there will be no vibration-guided breath work that follows. Instead, it'll be up to you to engage in the wellness practice of your choice for 3 minutes. At the end of 3 minutes, your device will vibrate once more to let you know which HRV zone you're ending your session in. Nudge mode is useful for individuals who do not wish to engage in a vibration-guided breathing exercise due to sensitivity to the haptic feedback, or a desire to engage in a different wellness practice other than the ones provided in the Lief app.
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Please keep in mind that the core exercise specifically designed to increase your HRV, and the main objective of the Lief program, is Downtime. By syncing your heart rate with your breath, the Downtime practice sends a biofeedback signal to your brain that you are safe and can relax, thus restoring your nervous system by activating the parasympathetic mode.