Accurate VO2 Max for Zwift and Strava

Anyone fancy making their own cheap device?

https://www.instructables.com/Accurate-VO2-Max-for-Zwift-and-Strava/

Quote:

The device also easily pairs with the Strava app for providing VO2 Max data for all your trail excursions. It substitutes VO2 max information for the heart rate sensor data in both of these popular exercise programs. The device is portable and lightweight with Wifi and Bluetooth capabilities and is easily worn with a modified 3M mask designed to be comfortable for long term use. I have tested the device for other sports including cross-country skiing and skating but its portability and wireless transmission capacity make it amenable to just about any sport other than swimming. The device also communicates with an App for the iPhone which enables graphing and long term data storage and download for ancillary calculations. The output includes continuous output of VO2, calories consumed, volumes of expired gas, as well as performing such functions as Basal Metabolic Rate. The device is easily made for about $100. Parts are all readily available and the case is 3D printed. It can be assembled in about 10 minutes. We tested the device in a physiology lab against a $60,000 machine and found it gave the about the same results.