Hi all. Reading through this, I feel like I'm late to the party, and many of the guests have already gone home!
I've been using Visible Plus, with the Polar armband for around three weeks now. I feel like I learned a fair bit about myself in the first few weeks. Firstly, I was amazed at which activities send me into "Over Exertion" most rapidly. My morning rituals (probably more like midday most days) of shower or bath, shaving, brushing my teeth and dressing seem to wipe me out more than almost anything else. Which kind of explains why I find the rest of the day so hard, and why it's so easy to trigger PEM. Being able to compare activities like a short walk or short drive (I'm only mild to moderate at present fortunately) against a shower has been a real eye opener.
I feel that there are (at least) two limitations however:
1) Regarding cognitive energy monitoring and associated malaise, which it clearly can't monitor directly. If I am writing an email or filling out a form that's emotional, that often raises my heartbeat, but if I'm trying to work something out involving numbers, that can just as easily send me into brain fog without any rise in heart rate, so I need to bear that in mind.
2) I confess to being totally confused about how "Pace Points" are supposed to reflect the amount of exertion! I've looked at the Workwell HRM Factsheet, which basically seems to advise keeping your heartrate below a threshold is called the ventilatory/anaerobic threshold, or V/AT for short, which is generally calculated as you resting heart rate plus 15 bpm, and suggests stopping an activity completely if you exceed this for 2 minutes. Looking at the Visible App approach, the thresholds are set to "Activity" which is a little higher (maybe 8-10bpm) than your resting heart rate, and an "Over Exertion" threshold which is 15 higher than that. Now comes the odd bit - You seem to run up "Pace Points" based on simply the time spent (per minute) in "Activity" and 4 x time spent when in "Over Exertion". But once in over exertion, it doesn't seem to matter how high you send your heart rate, you don't run up Pace Points any faster. So in theory if I enter "Over Exertion" when walking slowly, but also when walking rapidly, if I'll run up the same number of points walking slowly as I would walking rapidly, but I know that the second wears me out MUCH more, and I would prefer that to be reflected in the points. If not, it would appear that the best way to keep my pace points down is to run everywhere, because I'll spend less time running than I would walking because I would get there quicker!
So I'm interested in comments on Pace Points, and whether people are persevering and what experience you are having please. I agree with some earlier comments on the measures of HRV seem quite random, and the guidelines on how well my day is likely to progress don't tie in very will with my perceived fatigue and PEM state.