First of all, what is VO2 max and how do you measure your personal VO2 max? Here’s a quick FAQ on VO2 Max.
The only accurate way to measure VO2 max is to wear a face mask and actually measure the amount of oxygen flowing through the mask and to your lungs. Obviously, the Apple Watch doesn’t come with a face mask attachment you can connect via Bluetooth, yet. So how does Apple Watch measure V02 Max?
Apple watch uses a metric known as “Predicted V02 Max” and is based on your heart rate activity during exercise. Since the relationship of the heart rate and the VO2 max varies between everyone, it’s not a perfect indicator of your VO2 max, but with regular testing, you can see the trends of improvement or decline in relation to your own VO2 max baseline.