@cl-user thanks, this is very helpful indeed.
Have you tried the Moxy? Seems to be less “invasive” easier to wear? Besides that advantage what would you say the pros / cons of Moxy vs Calibre are in the context of optimal Zone 2 and Zone 5/Max VO2 type of training?
@Neo I really do like the Moxy because it’s both usable to find your zones and thresholds with a power ramp test for instance but also as I mentioned it’s usable during runs while Calibre is indoor only.
That said Calibre will also measure VO2 and plenty of other parameters so both are useful.
The thing that surprised me the most with Moxy is the importance of a proper warmup both in quality and duration. Before I would warmup by running at low speed for 10 min then think I’m OK and continue. That does not work at all. When I do that the oxygen in the muscle is at 40~50% only and will mostly stay there for the whole run which is not optimal.
The optimal way do warmup for my N of 1 is walking 1min then running at slow pace 5min and repeating that 3 or 4 times with a 30s sprint after the second series. Doing that protocol will bring the oxygen in the muscle is to 70~80% and if I stay in Z2 it will go down slightly but still be much higher than without a proper warmup.
As I said I was really surprised to see that starting with a bad warmup would stay suboptimal and I used to think that running would complete the warmup and end at the same point.
I also tried a lot of things to try and shorten that warmup time but so far nothing has worked. Basically it always takes 20 ± 5 min whatever I try. Probably it’s the time needed to dilate the capillaries, bring up the nutrients and oxygen, start the mitochondria, etc.
There is plenty or scientific research that uses those sensors and there is a small Moxy conference every year.
BTW in addition to those sensors you also need to measure the power as those thresholds will be defined by some output power. You can’t rely on the heart rate which is not precise enough and lagging too much. I use Stryd for running.
Interesting… I’m just learning about this entire area:
It strikes me there is useful data to be obtained here. The question is what is the best mechanism.
@John_Hemming It depends your primary focus.
If it’s sport performance then Moxy is better because it measure oxygen in the muscles where it matter most for exercise and as I mentioned you can use it in real time while exercising.
If it’s metabolism in general then Calibre is better as it will give you more direct measurements of your metabolic state like the carbs/fat burn rates, etc.
There is an overlap for finding the cardiovascular zones but otherwise they complement each others and you need both.
I’m not (by far!) one of those using the highest number of supplements and medications but I’m probably one of those with the highest number of sensors 
Could you please list them?
I am quite into testing. Sadly I have concluded that Aktiia is not worth persisting with. However, I would quite like something in this territory.
Moxy sensor: Muscle oxygen, muscle hemoglobin
Stryd foot pod: Running power, critical power, various running dynamic parameters, VO2
RunScribe foot pods + sacral pod: tons of running dynamic parameters, VO2
Keto-Mojo: Blood glucose + blood ketones
BioSense: Breath ketones meter
Contour Next ONE: Blood glucose
Various GCM on and off: Dexcom G6/7 and/or Abbott Libre3
Muse: EEG (Brain waves, Neurofeedback meditation)
Mendy: NIRS like Moxy but for the brain (Neurofeedback training)
Eight Sleep Pod: Regulates bed temperature (sleep phases, HR, HRV, respiration)
Calibre: Ordered, Waiting for it
More mainstream:
Garmin EPIX pro: HR, HRV, ECG, temperature, altitude, blood oxygen, sleep phases, respiration, etc.
Garmin HRM pro: Heart rate band
Polar H10: Heart rate band + ECG
Oura ring: HR, HRV, temperature, blood oxygen, sleep phases, respiration.
Withings Body Scan scale: Weight, Bio impedance (segmental body composition, fat, visceral fat, lean tissue, water), 6-Lead ECG and Vascular Age, electrodermal activity assessment.
OMRON BP: blood pressure
I though Muse was quite good, but I found it a faff keeping it on my head whilst sleeping so I gave up with using it. It is, however, really good.
Polar H10 is good. I use Fitbit rather than Garmin/Oura and I am not a fan of Withings sleep systems. I have used Dexcom G6 and G7 and Libre 2. I prefer Dexcom. I also use Omron for BP. I have stopped keeping Aktiia on my wrist.
Otherwise you give an interesting and impressive list to try out
Deleted as asked and already answered
You win the award for the most quantified self I’ve ever seen! Well done. I love the effort.
Some links for others like me who want to investigate these.
When you say “Mendy”, I think you mean this: https://www.mendi.io
I’ll just add this to the list. I found this recently. Looks like another really interesting piece of equipment.
More by Alan C:
https://twitter.com/alan_couzens/status/1741831602932498518?s=46&t=zJMJ1xVdRJYEDYz-DHipTw
And from another guy who seems to know what he is talking about:
https://twitter.com/feelthebyrn1/status/1737610369185595535?s=42&t=zJMJ1xVdRJYEDYz-DHipTw
Hi Joesph, have you heard anything back yet?
No but I’ll follow up.
Thanks 
appreciated
Btw have you ever done any zone 2 lactate calibration testing at home?
No. I have always relied on the “talk test” or nasal breathing minus a cushion to keep me under my zone 2 limit. It’s a rough estimate but it works (I’m confident) because I am no longer tempted to ride hard for a “good workout “.
Yeah, that + some heart rate triangulation is what I’ve done so far too.
Buy give that I’m now doing a couple of hours a week I wonder if it would be worth to invest the effort to calibrate with the lactate sticks one a month or something.
Do you have any sense of whether it is better to err on the side of being below or above zone 2 when one is targeting it?
Yes. Definitely better to be below the LT1. Below the threshold between zone 2 & 3. In fact, fat max is often in zone 1 if you are a fit but non elite athlete.