Originally Posted by
terrymorse
Why do you need a 4 lead sensor to measure HRV? It seems like a very easy thing to measure.
From the Apple Health app:
R-Rs are fairly simple to measure, only thing is, they aren't very interesting. What I watch particularly, the best gauge of my readiness level, is my standing HF (parasympathetic) power. I also watch the sum of my resting and standing SDNNs.
Edit: the other and more important issue is the reliability of the reading. If your heart does a reset or drops a beat, as happens to many fit people, and you have no visual of your cycle of R-R's, you won't know that happened. Those events have a major effect on HRV numbers and all the various stats associated with them. it can be hard or impossible to know if the number you're seeing reflects your reality or is just a glitch.