HRV and Forerunner 55

Question about the Forerunner 55. My body battery is pretty much always low, even after a restful day and good sleep. Looking on forums, it looks like body battery is based on stress levels, and stress levels are based on heart rate variability. However, the Forerunner 55 doesn't calculate HRV (not even in the garmin connect app). So how does this device calculate stress, body battery, etc. if it can't measure HRV?

0 9385703 4 months ago

I think this is the most definitive answer:

https://www.firstbeat.com/wp-content/uploads/2015/10/Stress-and-recovery_white-paper_20145.pdf

TLDR: it kind of does, but I guess it still outputs anomalous or difficult to interpret results a small portion of the time, so they thought their model for estimating physiological stress would be more useful. I guess in your case maybe check the resting and maximum heart rate look okay, and make sure to enter your age, gender, height and weight, since that is all probably used in their model.