No I was absolutely talking about heart rate variability in my comment and I wasn't confused by the term. The article was talking about wearables being able to

No I was absolutely talking about heart rate variability in my comment and I wasn't confused by the term. The article was talking about wearables being able to measure these types of metrics and what average people do in response to those metrics. The article spoke about a Ring which indicated to the author that they were becoming sick, this watch also uses HRV and uses HRV amongst other metrics to determine things like illness. Yes wearables measure both HR and HRV, I was talking specifically about HRV.