I was looking at the Calibre but it seems more smoke and mirrors and that they’re selling an appearance of precision. Like Lumen. I thought Kardiocoach was not very accurate based on some literature I read before.

I don’t have a lot of experience with medical-grade carts unfortunately. I paid 10x more ($5k USD) for a Pnoe cart and it’s not very repeatable or accurate, even with gas calibration. I expected this behavior when paying 1/4 of a lab-grade cart price.

VO2Master seems to be doing well, but it’s O2 only.

I find it difficult to believe that metabolic cart tech has come this far so fast that $500 will get you any reasonable readings. Cosmed and Vacumed portable carts are still very expensive, and for good reason.

I used a vo2master for 2years and it just never seemed to be accurate. Even after servicing (which was expensive).
In the end I contacted them and they told me the hardware was outdated and I should use the hardware until it stops working and buy a new one. For the price i don’t expect to buy a new device every 3 years.

Edit: we crossreferenced the vo2master with data from a medical grade machine at a university.

I haven't had a proper VO2max test for about 10 years (university physio lab) and can't comment on the Calibre or others; however, there was an interesting thread on Hacker News not too long ago - https://www.instructables.com/...or-Zwift-and-Strava/ - which, if you're inclined on the DIY side, looks like a not-too-bad investment of about $100.

I have the $100, just don't have the patience and equipment to, well, do it myself. But anyway, some might find it useful.

At certain point during ramp tests it (KORR) would give odd or anomalous data at the top end....not sure if error, structure of ramp, sampling rate average etc. We stopped doing ramp tests very early on because things like VT(s), event specific maxlass (threshold) can be more easily and accurately determined via steady state. (and BL)...regardless of 50k$ vs 1-10k$ equipement

...IE calculating substrate utilization and using that data to inform Fuel plans for IM, Ultra running, Ultraman 3 day etc....thats what we used it for.

Maurice

That’s a shame to hear, but not surprising. And I’m shocked that they won’t upgrade the hardware.

Pnoe claims their device is good for 12 years with the O2 sensor being replaced every 24 months. I’m grandfathered into a low price for service, but now Pnoe charges about half the price of the unit for service…so you’re effectively buying a new unit every four years.

I’m a hobbyist, so dropping 20k on a cart is not ideal. But I have considered it for the data quality that I want.

....that is insane....! I'm always amazed at what certain types of people can do given a bit of spare time.

Maurice

I’ve studied Pnoe’s patent and their device is really simple. It’s a MEMS flow sensor, peristaltic pump, O2 and CO2 sensor and a microprocessor and some ancillary stuff. I’ve even discussed the device with the inventor, although he wouldn’t answer ALL of my questions.

I found the manufacturer for the MEMS flow cell, but I haven’t found O2/CO2 sensors with the fast response time and high accuracy needed for breath-by-breath analysis.