The last month or so I've taken a few HRV scores in a row, separated by a few minutes in the same seated resting position I took the first in.
I've noticed that I can get anywhere from 5 to 15 point swings in my daily reading when taking a few readings back to back.
For example, I just took my first reading of the day (same time as most days and I usually only take one reading per day) and I got a score of 75. That's the upper range for me. I accidentally hit the Chart page before saving my score so I lost that reading on my iPhone. Three minutes later, without moving I took another reading and got a score of 61.
This seem to me to be a large variance in such a short time span. Does anyone have any idea why this happens?
the same is true for me. i tried a few times now. after waking up, i took 3 scores consecutively. the hrv jumped more within these 9 minutes than from one day to the next!
This realy leaves me in doubt, if the accuracy is anywhere good enough to guide my training. :(
Please do not leave this post unanswered, since it is not the only one describing this phenomenon. And please, if possible, provide some explanation other than simply "stick to the first reading it is accurate".