Rhonda Patrick· PhD
my my I use another app that checks my HRV every single morning and it predicts my zone 2 as a result of my HRV and so every day what I'm doing is I'm looking at the heart rate predicted by the app which can vary by as much as 10 beats per minute based on how much I slept the quality of my sleep how sore I am a subjective measurement of how much I want to train that day and my HRV